At present, there are conflicting data on the ability of echocardiographic parameters to predict the exercise-induced elevation of left ventricular (LV) filling pressure. The purpose of the present study was to validate the ratio of early diastolic transmitral (E) to mitral annular velocity (e′) obtained at peak exercise in its capacity to determine the exercise-induced elevation of pulmonary capillary wedge pressure (PCWP) and to reveal new noninvasive parameters with such capacity.
Sixty-one patients who had undergone heart transplantation with normal LV ejection fraction underwent simultaneous exercise echocardiography and right heart catheterization.
In 50 patients with a normal PCWP at rest, exercise E/e′ ≥8.5 predicted exercise PCWP ≥25 mmHg with a sensitivity of 64.3% and a specificity of 84.2% (area under the curve [AUC]=0.74). A comparable or slightly better prediction was achieved by exercise E/peak systolic mitral annular velocity (s′) ≥11.0 (sensitivity 79.3%; specificity 57.9%; AUC=0.75) and exercise E/LV systolic longitudinal strain rate ≤−105 cm (sensitivity 78.9%; specificity 78.6%; AUC=0.87). Combined, exercise E/s′ and exercise E/e′ resulted in a trend toward a slightly more precise prediction (sensitivity 53.6%; specificity 89.5%; AUC=0.78) than did either variable alone.
Exercise E/e′, used as a sole parameter, is not sufficiently precise to predict the exercise-induced elevation of PCWP. Exercise E/s′, E/LV systolic longitudinal strain rate or combinations of these parameters may represent further promising possibilities for predicting exercise PCWP elevation.
Diastolic function; Exercise echocardiography; Pulmonary capillary wedge pressure
To investigate the feasibility and safety of using sheathless standard guiding catheters for transradial percutaneous coronary intervention (PCI) to treat bifurcation lesions.
Coronary bifurcation lesions were identified using angiography in 43 patients with coronary artery disease. These patients underwent transradial PCI using sheathless standard guiding catheters, and the procedural success and complication rates were recorded.
All 43 patients underwent successful PCI. The Culotte stenting technique was used in 22 (51.2%) subjects, the Crush stenting technique was used in eight (18.8%) subjects and the crossover stenting implantation technique was used in 13 (30.0%) subjects. Of the 43 coronary artery bifurcation lesions, the final kissing balloon technique was performed in 39 (90.1%) lesions. Adjunctive devices used in the cohort included intravascular ultrasound for 32 (74.4%) patients, thrombus aspiration catheters for two patients and cutting balloon for five patients. During the perioperative period, no major complications associated with vessel puncture or adverse cardiac or cerebrovascular events occurred in any of the 43 patients enrolled in the present study. At day 30, radial artery occlusion was detected in only three (2.5%) patients and radial artery stenosis in four (9.3%) patients. At six-month follow-up, 24 (55.8%) patients exhibited coronary artery patency with no significant intimal hyperplasia.
Transradial PCI using the sheathless technique may be a feasible and safe technique to treat coronary bifurcation lesions.
Bifurcation lesions; Percutaneous coronary intervention; Radial artery; Sheathless
Although seasonal variation in hospitalizations due to chronic heart failure is recognized, the possible contributors to such variability are less well documented.
Records from all admissions to 12 hospitals in Hubei province, China, over a 10-year period with diagnostic codes for chronic systolic heart failure (CSHF) were reviewed. A total of 16,145 patients with CSHF were analyzed.
There was a marked seasonal variation in the number of hospitalizations due to CSHF, with two peaks in the monthly rate of hospitalization due to CSHF occurring in December and August compared with the spring and autumn months. Monthly hospitalizations due to CSHF for patients with New York Heart Association class III and IV ranged from a peak of 40.4% and 23.3% above average in December and August, respectively, to 18.6% below average in November, while hospitalizations due to CSHF for patients with New York Heart Association class I and II exhibited no obvious seasonal variation. Blood sodium level (95% CI 2.132 to 2.144; P=0.036) was an independent risk factor for hospitalizations due to CSHF in August.
The number of hospitalizations due to CSHF increased during the colder and warmer months in China. A low blood sodium level was associated with the peak in hospitalizations in August.
Blood sodium; Cardiac function; Chronic systolic heart failure; Hospitalization; Seasonal variation
It is well known that nitrates can induce paradoxical myocardial ischemia.
METHODS AND RESULTS:
Fifty patients (median age 73 years; range 67 to 78 years; 80% male) with healed myocardial infarcts were selected. All patients underwent resting single-photon emission computed tomography (SPECT) and resting baseline gated-SPECT using sestamibi or thallium-201 after the sublingual administration of 5 mg isosorbide dinitrate (ISD). Forty-eight per cent (24 of 50) of the patients demonstrated ISD-induced peri-infarct ischemia as observed by SPECT. Compared with patients without ISD-induced ischemia, patients with ISD-induced ischemia presented larger infarcts as determined by the extent of perfusion defects (mean [± SD] 27±12 pixels versus 11±9 pixels; P<0.0001), lower ejection fractions (39±17% versus 50±15%; P<0.02) and a higher incidence of severe coronary artery disease (P<0.04). At five years, the survival probability on Kaplan-Meier analysis was 42% and 96% for patients with and without ISD-induced ischemia, respectively (HR 5.6 [95% CI 1.6 to 20]; P=0.009).
Nitrates may have low efficacy in improving blood flow through the coronary vessels that supply large myocardial infarcts with high-resistance microvascular damage. At the same time, nitrates induce dilation and blood pressure decrease in remotely patent or mildly stenotic vessels. The blood pressure gradient elicited between the high- and low-resistance coronary vessels may provide the force for a blood flow steal from the viable zones of the infarct toward the healthy myocardium. The resultant nitrate-induced paradoxical ischemia could be a silent marker of myocardial instability and adverse outcomes in elderly patients with healed myocardial infarcts.
Healed myocardial infarct; Nitrate paradoxical ischemia; SPECT imaging
The clinical outcome of patients with myocardial infarction (MI) complicated by cardiogenic shock (CS) who require mechanical ventilation (MV) is poor.
To analyze the impact of abciximab pretreatment in this high-risk population of MI patients.
The present study was a retrospective subanalysis of the multicentre randomized Routine Upfront Abciximab Versus Standard Peri-Procedural Therapy in Patients Undergoing Percutaneous Coronary Intervention for Cardiogenic Shock (PRAGUE-7) study, which included 80 MI patients in CS undergoing primary percutaneous coronary intervention (PCI). Patients were randomly assigned into group A (routine pretreatment with an abciximab bolus followed by a 1 h abciximab infusion) and group B (standard therapy). The subanalysis included 37 patients requiring MV. Seventeen patients were in group A and 20 were in group B. The primary end point (death/stroke/reinfarction/new severe renal failure) at 30 days, procedural success (thrombosis in myocardial infarction [TIMI] flow) and frequency of bleeding were assessed. The χ2 and Student’s t tests were used for statistical analysis; P<0.05 was considered to be statistically significant.
The primary end point occurred in nine (53%) patients in group A and 12 (60%) patients in group B (P=0.66). TIMI flow after primary PCI was higher in group A (2.75 versus 2.31; P<0.05). Major bleeding occurred in 12% of patients in group A versus 10% of patients in group B (P=0.86). Minor or minimal bleeding was more common in group A (29%) compared with group B (5%; P<0.05).
The results of the present study suggest that routine pretreatment with abciximab before primary PCI in mechanically ventilated patients with MI complicated by cardiogenic shock was associated with better angiographic results but also with a higher incidence of bleeding.
Abciximab; Acute coronary syndrome; Cardiogenic shock; Intensive care; Mechanical ventilation; Percutaneous coronary intervention
To evaluate whether pacing or sensing configuration has an effect on pacing parameters or their time progression. Three left ventricular (LV) pacing parameters were monitored – the LV pacing threshold, pacing impedance and intrinsic R-wave amplitude.
Data were collected at three intervals: during implantation; between the second and fifth month after implantation (first follow-up); and between the eighth and 15th month after implantation (second follow-up). Repeated-measures ANOVA was used for the statistical analysis.
The impedance, but not its time progression, was significantly higher for the LV tip to LV ring configuration than for other configurations. R-wave amplitude and impedance increased significantly (without dependance on configurations) between implantation and first follow-up, as expected. The time progression of any parameter was not dependent on configuration of the LV lead.
LV tip to LV ring is the best configuration for maintaining a high impedance level. It is better to maintain an individual approach for pacing threshold and R-wave amplitude, and their settings.
Cardiac resynchronization therapy; Impedance; Left ventricular pacing threshold; Repeated measures ANOVA; R-wave voltage
Hypertension has become prevalent among young and middle-age individuals. Many studies have identified a variety of risk factors for cardiovascular diseases, yet there have been few reports focusing on the young and middle-age hypertensive population.
To investigate the epidemiological characteristics of conventional risk factors of premature coronary artery disease (PCAD) in patients with hypertension.
The clinical and laboratory data of 267 hypertensive patients with PCAD and 96 hypertensive patients without any visible coronary disease according to angiography were compared. Potential coronary risk factors were analyzed using logistic regression.
The PCAD group had lower levels of high-density lipoprotein cholesterol (HDL-C) (P<0.05). Multivariate logistic analysis showed positive family history, low HDL-C, hypertriglyceridemia, duration of diabetes mellitus and male sex were significantly associated with PCAD (P<0.05), with ORs of 12.317, 3.267, 2.894, 1.140 and 0.088, respectively. Plasma renin activities in PCAD patients were significantly higher than in control hypertensive patients (P=0.027), but there was no significant difference in angiotensin II and aldosterone levels between the two groups.
Low HDL-C and hypertriglyceridemia are important coronary risk factors in Chinese individuals with hypertension.
Hypertension; Hypertriglyceridemia; Low HDL cholesterol; Premature coronary heart disease
Aortic dilation may critically precede progression to thoracic aortic aneurysm (TAA). Prolonged or repetitive isometric-type heavier strenuous activities resulting from the nature of some professions may be an important causative factor for TAA.
The echocardiographic measurement data of middle-age subjects who were isometric-type daily strenuous activity trainers or ordinary activity trainers were retrospectively analyzed. Clinical features and echocardiographic parameters of the left ventricle and left atrium (LA), aortic root (AR) and ascending aorta (AA) were compared between the groups.
AR (35.6±3.0 mm versus 33.5±1.9 mm), AA (36.8±3.0 mm versus 34.4±1.9 mm) and LA (37.4±2.2 mm versus 36.2±2.2 mm) diameters were significantly enlarged in the strenuous activity trainer group versus the ordinary activity group. Diastolic blood pressure was significantly lower (73.8±5.9 mmHg versus 78.3±6.0 mmHg) in this group. AR diameter was correlated with height (β=0.460; P=0.004) and LA diameter (β=0.280; P=0.008) while AA diameter was correlated with type of profession (β=0.309; P=0.003), left ventricular systolic diameter (β=0.500; P=0.001) and LA diameter (β=0.272; P=0.005) in regression analysis.
Aortic dilation and, subsequently, TAA may be an occupational disease due to nature of some professions (eg, the military, security, weight lifters, athletes, heavy workers, etc). Echocardiography is a convenient method of imaging that could be easily applied either during preparticipation screening or during periodical examination of these subjects. Earlier detection of TAA and limitation of such strenuous activities in these individuals may be initial lifesaving measures for the prevention of future cases of aortic aneurysm and dissection.
Aortic aneurysm; Echocardiography; Occupation; Strenuous sports; Weight lifting
Several imaging tests and biomarkers have been proposed for the identification of patients with unstable angina among those presenting to the emergency department with acute chest pain. Preliminary data suggest that ischemia-modified albumin (IMA) may represent a potentially useful biomarker in these patients.
To compare IMA and echocardiography in excluding unstable angina in patients with acute chest pain.
Thirty-three patients (mean [± SD] age 59.8±10.8 years; 28 men) presenting to the emergency department with acute chest pain lasting <3 h suggestive of acute coronary syndrome, with normal or non-diagnostic electrocardiograms, and creatine kinase MB and troponin levels within the normal range, were included in the present study.
After further diagnostic evaluation, five patients (15.2%) were diagnosed with unstable angina. The sensitivity, specificity, positive predictive value and negative predictive (NPV) value of echocardiography for diagnosing unstable angina was 60.0%, 89.3%, 50.0% and 92.6%, respectively. The area under the ROC curve for diagnosing unstable angina based on the serum IMA levels was 0.193 (95% CI 0.047 to 0.339; P<0.05). Based on ROC curve analysis, serum IMA levels ≥31.95 IU/mL yielded the optimal combination of sensitivity and specificity for diagnosing unstable angina. The sensitivity, specificity, positive predictive value and NPV of serum IMA levels ≥31.95 IU/mL for diagnosing unstable angina was 40.0%, 28.6%, 9.1% and 72.7%, respectively.
Measurement of serum IMA levels appears to represent a useful tool for excluding unstable angina in patients presenting to the emergency department with acute chest pain. Moreover, IMA shows an NPV that is comparable with echocardiography.
Acute chest pain; Acute coronary syndromes; Echocardiography; Ischemia-modified albumin; Unstable angina
Quality assurance in atrial fibrillation is related to the appropriate use of anticoagulation. The CHADS2 score is widely used to determine which patients should or should not be anticoagulated. The authors hypothesized that as thromboembolic risk and, therefore, the CHADS2 score increases, so should the rate of anticoagulant prescription. The authors found a positive correlation between CHADS2 score and anticoagulant prescription (r=0.8) in a mini-survey.
Although anticoagulant use at CHADS2 score = 0 was presumed to be very low, it was found to be higher than expected. This was readily explained by a group of low-risk patients being anticoagulated before cardioversion. Cardioverted patients were then examined as a group and it was found that the rate of rhythm control decreased with CHADS2 score (r= −0.89), a finding that has not been reported in the literature and may warrant further investigation.
Anticoagulation; Atrial fibrillation; Cardioversion, CHADS2 score; Quality assurance in cardiology
Systemic thromboembolism is a serious, major complication in patients with an atrial septal aneurysm (ASA). Atrial dysfunction resulting from paroxysmal atrial fibrillation is more common in patients with ASA than in the general population. The autonomic nervous system plays an important role in the initiation of atrial fibrillation.
To investigate autonomic function and its impact on ventricular and atrial arrhythmia in a group of ASA patients compared with a control group of healthy volunteers.
The study group consisted of 40 patients with ASA; the control group consisted of 30 age-, sex- and body mass index-matched healthy volunteers. All patients and control subjects underwent echocardiographic examination. Autonomic function was assessed by determining heart rate variability (HRV) indexes.
HRV time and frequency domain indexes were lower in patients with ASA compared with healthy controls (188±32 ms2 and 323±42 ms2 for low-frequency HRV; 195±39 ms2 and 377±43 ms2 for high-frequency HRV; P<0.001 for all). Statistically significant differences with respect to other HRV indexes were also found between the two groups.
ASA appears to be associated with cardiac autonomic dysfunction; however, the mechanisms of this association are not known in detail.
Arrhythmia; Atrial septal aneurysm; Autonomic nerve system; Heart rate variability
The development of acute renal injury (ARI) is an important indicator of clinical outcomes after cardiac surgery. Neutrophil gelatinase-associated lipocalin (NGAL) has been certified as a predictive biomarker of hypoxic ARI. The present study aimed to determine the predictive role of NGAL in coronary bypass graft (CABG) surgery.
A total of 72 consecutive patients undergoing elective CABG were enrolled in the study. NGAL levels were determined preoperatively and postoperatively after 6 h, 24 h and 72 h for all participants. The participants were then divided into two groups according to their preoperative creatinine levels (group I, creatinine 111.38 μmol/L to 361.55 μmol/L; group II, creatinine <111.38 μmol/L).
There was no statistically significant difference between the groups according to their NGAL values (P>0.05), except at 6 h (P=0.045). Three patients required continuous hemodialysis. Comparison of the NGAL levels of these three patients with those of the other participants did not reveal any correlation with serum creatinine levels. In contrast, the NGAL levels were significantly lower in the continuous hemodialysis patients (1.9±1 ng/mL) compared with those of the other participants (22.6±12.8 ng/mL; P=0.001).
NGAL is one of the most frequently used biomarkers for ARI after cardiac operations, especially in younger patients. The participants in the present study were coronary artery disease patients and were, therefore, older than patients in previous reports. These results support the view that NGAL is not a relevant predictive factor for ARI in patients with CABG, including older patients.
Acute renal injury; Bypass; NGAL; Predictive role
QT and P wave dispersion parameters can indicate abnormalities in autonomic nervous system and cardiac functioning.
To determine QT and P wave dispersion in patients with major depressive disorder compared with healthy volunteers.
Fifty newly diagnosed patients with major depressive disorder and 50 age- and sex-matched healthy volunteers underwent 12-lead electrocardiography. QT interval, QT dispersion, heart rate-corrected QT dispersion and P wave dispersions were calculated manually by a blinded specialist.
Groups were comparable in terms of age, sex, body mass index, smoking status, metabolic diseases and left ventricular ejection fraction. The major depressive disorder group had significantly higher QT dispersion (58.5±9.9 versus 41.7±3.8; P<0.001), heart rate-corrected QT dispersion (62.5±10.0 versus 45.2±4.3; P<0.001) and P wave dispersion (46.9±4.8 versus 41.5±5.1; P<0.001).
Increased QT dispersion, heart-rate corrected QT dispersion and P wave dispersion in major depressive disorder patients may be indicative of autonomic imbalance and increased risk of cardiac morbidity and mortality.
Autonomic nervous system; Cardiac function; Cardiovascular diseases; Depression; Electrocardiography
Patients hospitalized for decompensated heart failure (DHF) frequently experience worsening of renal function (WRF), leading to volume overload and resistance to diuretics.
To investigate whether albumin levels and whole-body impedance ratio, as an indicator of water distribution, were associated with WRF in patients with DHF.
Methods: A total of 80 patients hospitalized for DHF were consecutively included in the present longitudinal study. WRF during hospitalization was defined as an increase of ≥0.3 mg/dL (≥26.52 μmol/L) or 25% of baseline serum creatinine. Clinical and echocardiographic characteristics were assessed at baseline. Whole-body bioelectrical impedance was measured using tetrapolar and multiple-frequency equipment to obtain the ratio of impedance at 200 kHz to that at 5 kHz. Serum albumin levels were also evaluated. Baseline characteristics were compared between patients with and without deteriorating renal function using a t test or χ2 test. Subsequently, a logistic regression analysis was performed to obtain the independent variables associated with WRF.
The incidence of WRF during hospitalization was 26%. Independent risk factors associated with WRF were low serum albumin (RR=0.11; P=0.04); impedance ratio >0.85 (RR=5.3; P=0.05), systolic blood pressure >160 mmHg (RR=12; P=0.02) and maximum dose of continuous intravenous furosemide required >80 mg/day during hospitalization (RR=5.7, P=0.015).
WRF is frequent in patients with DHF. It results from the inability to effectively regulate volume status because hypoalbuminemia induces water loss from the vascular space (high impedance ratio), and high diuretic doses lower circulatory volumes and reduce renal blood flow, leading to a decline in renal filtration function.
Albumin concentration; Heart failure; Impedance index; Worsening renal function
The gold standard treatment for multivessel coronary revascularization is coronary artery bypass grafting. The internal mammary artery and saphenous vein grafts are the conduits most frequently used for these operations. Spasm of arterial and venous grafts is a significant problem during the operation.
To evaluate the acute in vitro effects of L-carnitine on internal mammary artery and saphenous vein grafts using a tissue bath.
Ten consecutive patients who underwent elective coronary artery bypass grafting were enrolled in the present study (nine men, one woman; mean [± SD] age 62±9.1 years). Samples from left internal mammary artery and saphenous vein grafts were collected from each patient. Submaximal smooth muscle contraction was achieved by adding 1 μM phenylephrine, and L-carnitine was then added to the solution. The concentration-response curves of the vasodilation response were obtained.
In the internal mammary graft samples, the vasodilation response to L-carnitine was 64.3±11.1% at a concentration of 5 mM. In the saphenous vein graft samples, the vasodilation response to L-carnitine was 41.5±11.4% at a concentration of 5 mM. There was a statistically significant difference (P<0.001) between the response of the internal mammary artery and saphenous vein grafts in the in vitro tissue bath system.
These results indicate that L-carnitine is a potential vasodilatory drug for internal mammary artery and saphenous vein grafts.
Coronary artery bypass; Internal mammary artery; L-carnitine; Saphenous vein
Coronary artery anomalies are present at birth, but relatively few are symptomatic. The majority are discovered incidentally. In the present study, coronary angiograms performed in the authors’ centre (Ondokuz Mayis University Hospital, Samsun, Turkey) were analyzed to determine the prevalence and types of coronary artery origin and course anomalies.
Coronary angiographic data of 16,573 patients were analyzed. Anomalous origins and courses of coronary arteries were assessed.
Anomalous coronary arteries were detected in 48 (0.29%) of 16,573 patients. The origin of the circumflex (Cx) artery from the right coronary artery (RCA) or right sinus of Valsalva was the most common anomaly (28 patients [58.3%]). An anomalous RCA originating from the left anterior descending artery (LAD) or Cx artery was observed in six patients (12.5%). The left coronary artery originated from the right sinus of Valsalva in five patients, and the LAD originated from the RCA or the right sinus of Valsalva in five patients. The RCA originated from the left sinus of Valsalva in three patients and from an ectopic ostium in the ascending aorta in one patient.
The most frequent anomaly observed in the present study was related to the Cx artery, which is consistent with previous reports. Although coronary artery anomalies are rare, they may cause difficulties during coronary interventions or cardiac surgery and may occasionally result in sudden cardiac death. Therefore, the recognition and diagnosis of these anomalies is important and requires specialization in coronary angiographic techniques and other imaging modalities.
Coronary angiography; Coronary artery anomaly; Sinus of Valsalva
C-reactive protein (CRP) is a marker of systemic inflammatory activity and may be modulated by physical fitness. Treadmill exercise testing is used to evaluate cardiovascular health through different variables including exercise capacity, heart rate and blood pressure responses. It was hypothesized that CRP levels are associated with these variables in men and women without overt heart disease.
A total of 584 asymptomatic subjects (317 [54.3%] women and 267 [45.7%] men) were enrolled in the present study and underwent clinical evaluation. CRP levels in men and women were examined relative to clinical characteristics and to variables of treadmill exercise testing: peak heart rate, exercise systolic blood pressure, exercise time, chronotropic reserve and heart rate recovery at the first and second minutes after exercise. Multivariate analysis was performed using a log-linear regression model.
In women, exercise time on the treadmill exercise test (P=0.009) and high-density lipoprotein cholesterol levels (P=0.002) were inversely associated with CRP levels. Body mass index (P<0.001) and total cholesterol levels (P=0.005) were positively associated with CRP levels. In men, exercise time on the treadmill exercise test was inversely associated with CRP levels (P=0.015). Body mass index (P=0.001) and leukocyte count (P=0.002) were positively associated with CRP levels. CRP levels were not associated with peak heart rate, chronotropic reserve, heart rate recovery at the first and second minutes, or exercise systolic blood pressure.
These findings contribute to the evidence that CRP is lower in individuals with better exercise capacity and demonstrate that this relationship is also apparent in individuals without overt heart disease undergoing cardiovascular evaluation through the treadmill exercise test. Lowering inflammatory markers may be an additional reason to stimulate sedentary individuals with low exercise capacity in the treadmill exercise test to improve physical conditioning through regular exercise.
C-reactive protein; Exercise capacity; Exercise stress testing; Sex
Pulmonary embolism is an important clinical entity with considerable mortality despite advances in diagnosis and treatment. In the present article, the authors offer a comprehensive review focused mainly on epidemiology, risk factors, risk stratification, pathophysiological considerations and clinical presentation. Diagnosis based on assessment of clinical likelihood, electrocardiography, chest x-ray, D-dimer levels, markers of myocardial injury and overload, and blood gases is discussed in detail. Special attention is devoted to the clinical use of computed tomography, pulmonary angiography and echocardiography in the setting of pulmonary embolism.
Diagnosis; Epidemiology; Pulmonary embolism; Risk stratification
Acute pulmonary embolism (PE) bears a significant burden on health and survival. Rapid and accurate risk stratification and management are of paramount importance to ensure the highest quality of care. This present article summarizes currently available and emerging management strategies for the disease. The authors not only review current evidence regarding early therapy of acute PE, including supportive care, anticoagulation, thrombolysis, surgical and catheter-based treatment, but also the possible role of mechanical circulatory support in PE. The authors also discuss complications related to PE and its management.
Anticoagulation; Catheter-based management; Pulmonary embolism; Supportive care; Surgical embolectomy; Thrombolysis
Early and accurate diagnosis and a prompt initiation of treatment are critical for the prognosis of light-chain amyloidosis. The present article describes a case involving a 62-year-old patient who experienced unexplained, chronic diarrhea with negative duodenal and rectal biopsies. Serum immunofixation, a free light-chain assay, electrocardiography and echocardiography were performed after the patient developed syncope. The results of these diagnostic investigations showed characteristic signs of systemic amyloidosis. Cardiac and bone marrow biopsies confirmed the diagnosis of systemic light-chain amyloidosis. The chronic diarrhea was found to be due to an autonomic neuropathy of the enteric nervous system.
Amyloidosis; Chronic diarrhea; Diastolic heart failure; Infiltrative cardiomyopathy; Peripheral neuropathy; Smoldering plasmacytoma
The chronic effects of ganglionic plexi (GP) ablation on atrial fibrillation (AF) inducibility have not been elucidated.
To investigate the effect of Wenxin Keli (WK) on the inducibility of AF and atrial substrate remodelling after epicardial GP ablation.
Twenty dogs were randomly divided into a sham-operated group, a GP ablation group and a WK-treated group. All animals underwent a left thoracotomy at the fourth intercostal space. AF inducibility was assessed by burst rapid pacing at the right atrium. Both the GP ablation group and the WK-treated group received four major GP ablations. In the WK-treated group, dogs were treated with oral WK once per day, and all animals were allowed to recover for eight weeks, after which AF inducibility and AF duration were measured again.
After eight weeks of WK treatment, AF inducibility was lower than in the GP ablation group, and was similar to that of the sham-operated group. Compared with the sham-operated group, the levels of atrial natriuretic peptide (ANP), tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-6 in right atrial tissues were increased in GP ablation group (143.6±33.7 pg/mg versus 206.2±41.4 pg/mg, P=0.02; 75.3±12.1 pg/mg versus 141.3±64 pg/mg, P=0.03; and 175.1±42.5 pg/mg versus 351.7±101 pg/mg, P<0.01, respectively). There were no significant differences in levels of ANP, TNF-α and IL-6 in atrial tissues between the sham-operated group and WK treated group. Expression of connexin 43 in atrial tissues was increased after eight weeks of GP ablation, while WK administration inhibited connexin 43 remodelling.
Epicardial GP ablation can induce atrial substrate remodelling, including Cx43 upregulation and increased levels of ANP, TNF-α and IL-6. These changes may be suppressed by long-term oral WK administration.
Ablation; Atrial fibrillation; Ganglionic plexi; Wenxin Keli
Previous studies using isolated mitochondria have provided new insight into the mechanisms and interventions for ischemia and reperfusion (I/R) injury. In in vitro experiments involving isolated mitochondria, hypoxia and reoxygenation (H/R) has been widely used to mimic I/R injury. However, in in vitro H/R mitochondrial experiments, the effects of various substrates on mitochondrial oxidative phosphorylation are unclear. In the present study, the effects of in vitro I/R injury on mitochondrial oxidative phosphorylation under different substrate conditions were investigated.
Hypoxia was achieved following complete consumption of oxygen by mitochondria isolated from rat heart tissue in an experimental chamber. The H/R protocol involved 30 min hypoxia followed by 15 min reoxygenation in a chamber opened to the atmosphere. Mitochondrial respiration and respiratory control ratio (RCR) were measured.
When pyruvate/malate were used as substrates, H/R significantly decreased state 3 respiration (28.2±12 nmol O2/min/mg protein) and RCR (2.7±0.8) compared with the control (121.4±32.5 nmol O2/mg protein/min and 7.8±1.2, respectively). In contrast, when succinate was used without rotenone, H/R significantly increased state 3 respiration (57.0±11.2 nmol O2/mg protein/min) and RCR (2.0±0.3) compared with the control (48.2±12.3 nmol O2/mg protein/min and 1.3±0.2, respectively).
The present study demonstrated that mitochondrial oxidative phosphorylation can be modulated by H/R in vitro depending on substrate conditions.
Ischemia/reperfusion injury; Isolated mitochondria; Oxidative phosphorylation
To explore the effect of metoprolol on myocardial apoptosis and caspase-9 activation after coronary microembolization (CME) in rats.
Forty rats were randomly divided into four groups (n=10 each): a sham operation (control) group, CME plus saline (CME) group, CME plus metoprolol (metoprolol) group and caspase-9 inhibitor Z-LEHD-FMK (ZLF) group. CME was induced by injecting 3000 polyethylene microspheres (42 μm diameter) into the left ventricle during a 10 s occlusion of the ascending aorta. Echocardiography, terminal deoxynucleotidyl transferase dUTP nick end labelling and Western blotting were used to evaluate cardiac function, apoptosis and activation of caspase-9/caspase-3, respectively, 6 h after CME.
The echocardiographic parameters of left ventricular function were significantly decreased in the CME group compared with the control group (P<0.05); however, the metoprolol group and ZLF group showed significantly improved cardiac function compared with CME alone (P<0.05). Compared with the control group, the myocardial apoptosis rate and the levels of activated caspase-9 and -3 increased significantly in the CME group (P<0.05). Again, these effects were ameliorated by metoprolol and ZLF (P<0.05).
The present study demonstrates that metoprolol and ZLF can protect the rat myocardium during CME by inhibiting apoptosis and improving cardiac function, likely by inhibiting apoptosis/ mitochondrial apoptotic pathway. These results suggest that antiapoptotic therapies may be useful in treating CME.
Apoptosis; Caspase-3; Caspase-9; Coronary microembolization; Metoprolol
In the surgical treatment of acute aortic dissection, tissue glues are widely used to reinforce the adhesion between the dissected aortic layers. A new inflatable balloon device was developed to compress the dissected aortic wall during gluing to increase adhesion between the dissected layers. The present study used an ex vivo experimental animal model to test the hypothesis that this device is effective when gluing the true and false channels of dissected aortas.
In the ex vivo experimental model, aortic dissection was simulated surgically on 12 fresh bovine aorta samples. In six samples (group I), the inflatable balloon device was inserted into the aorta to reinforce and fuse the dissected layers during gluing. The other six fresh bovine aortic samples (group II) were compressed between the surgeon’s fingers during gluing. Aortic samples were evaluated and compared macroscopically and histologically.
In group I, adhesion between the dissected layers was easily achieved during gluing. All false cavities were perfectly closed, with no deleterious effects related to the device. In group II, the adhesion between the dissected layers was not complete and some false cavities remained patent.
The inflatable balloon device can increase the adhesive effect of tissue glues via homogenous compression of the dissected aortic layers. In addition, the balloon can prevent distal embolization of the glue.
Aortic dissection; New inflatable balloon device; Tissue gluing