The introduction of multiple treatments for cancer, including chemotherapeutic agents and radiation therapy, has significantly reduced cancer-related morbidity and mortality. However, these therapies can promote a variety of toxicities, among the most severe being the ones involving the cardiovascular system. Currently, for many surviving cancer patients, cardiovascular (CV) events represent the primary cause of morbidity and mortality. Recent data suggests that CV injury occurs early during cancer treatment, creating a substrate for subsequent cardiovascular events. Researchers have investigated the utility of noninvasive imaging strategies to detect the presence of CV injury during and after completion of cancer treatment because it starts early during cancer therapy, often preceding the development of chemotherapy or cancer therapeutics related cardiac dysfunction. In this state of the art article, we review the utility of current clinical and investigative CV noninvasive modalities for the identification and characterization of cancer treatment-related CV toxicity.
Chemotherapy-related cardiotoxicity; noninvasive imaging; cardiovascular imaging
To assess the frequency and prognostic utility of small, short duration left ventricular (LV) myocardial perfusion defects during dobutamine cardiovascular magnetic resonance (DCMR) stress imaging.
We performed first-pass contrast-enhanced DCMR at peak stress in 331 consecutively recruited individuals (aged 68±8 years, 50% men) at intermediate risk of a future cardiac event. Size, location and persistence of low signal intensity perfusion defects were recorded. Cardiac events were assessed by personnel blinded to imaging results for a median of 24 months after DCMR.
Among the fifty-five individuals (16.6%) who exhibited small (<25% myocardial thickness) and short duration (<5 frames in persistence) perfusion defects, diabetes was more prevalent (p=0.019) and no cardiac events were observed. Large, persistent perfusion defects were associated with coronary artery disease (CAD), prior myocardial infarction, and decreased LV function (p<0.001 for all) and increased 2-year risk of cardiac event (HR 10.3, p<0.001, CI 3.3–33.0).
In individuals with diabetes, hypertension, or CAD at intermediate risk for a future cardiac event, small, short duration DCMR perfusion defects are not associated with an increased 2-year risk of subsequent cardiac event.
coronary artery disease; dobutamine cardiac magnetic resonance; prognosis
Abnormal resting arterial stiffness is present in middle‐aged and elderly persons with abnormalities of fasting glucose (diabetes or impaired fasting glucose) and is associated with exercise intolerance. We sought to determine whether these same persons exhibited stress‐related abnormalities of arterial stiffness.
Methods and Results
We analyzed dobutamine magnetic resonance stress imaging results from 373 consecutively recruited persons aged 55 to 85 years with normal fasting glucose, impaired fasting glucose, or diabetes who were at risk for but without symptomatic heart failure. Personnel blinded to participant identifiers measured arterial stiffness (brachial pulse pressure/left ventricular stroke volume indexed to body surface area, the aortic elastance index [brachial end‐systolic pressure/left ventricular stroke volume indexed to body surface area], and thoracic aortic distensibility) at 80% of the maximum predicted heart rate response for age. Participants averaged 69±8 years of age; 79% were white, 92% were hypertensive, and 66% were women. After accounting for hypertension, sex, coronary artery disease, smoking, medications, hypercholesterolemia, and visceral fat, we observed an effect of glycemic status for stress measures of arterial stiffness in those with diabetes and impaired fasting glucose relative to those with normal fasting glucose (P=0.002, P=0.02, and P=0.003, respectively).
Middle‐ and older‐aged individuals with diabetes or impaired fasting glucose have higher stress measures of arterial stiffness than those with normal fasting glucose. These data emphasize the need for future studies with larger sample sizes to determine whether stress‐related elevations in arterial stiffness are related to exercise intolerance and future episodes of heart failure experienced by those with abnormalities of fasting glucose.
Clinical Trial Registration
URL: http://clinicaltrials.gov/. Unique identifier: NCT00542503.
arterial stiffness; diabetes; dobutamine; elderly
Cardiovascular magnetic resonance (CMR) and cardiac computed tomography (CCT) offer advantages for detecting left or right ventricular dysfunction in patients with or suspected of heart failure. CMR does not expose patients to ionizing radiation, and thus is well-suited for functional assessments and serial studies. CCT provides high spatial resolution, making it useful for the identification of coronary arteriosclerosis associated with ischemic cardiomyopathy. In this review, the clinical applications of CMR and CCT are individually discussed, with comparisons made between them to examine the strengths of each modality. The major techniques for each modality are outlined, as well as their uses for the evaluation of cardiomyopathy in heart failure patients with reduced left ventricular ejection fraction, preserved left ventricular ejection fraction, and valvular heart disease. Finally, we review the utility of CMR and CCT in determining which patients will benefit from cardiac resynchronization therapy.
Cardiovascular Magnetic Resonance; Cardiac Computed Tomography; Heart Failure; Cardiomyopathy; Valvular Heart Disease
To determine if low to moderate doses of anthracycline-based chemotherapy (Anth-bC) are associated with subclinical cardiovascular (CV) injury.
Cancer survivors that receive Anth-bC experience premature CV events. It is unknown whether low to moderate doses of anthracyclines a) promote early subclinical CV disease manifested by deteriorations in left ventricular ejection fraction (LVEF) or increases in aortic stiffness, or b) are associated with change in quality of life (QOL).
In 53 men and women with breast cancer, leukemia, or lymphoma, we assessed left ventricular volumes, LVEF, circumferential strain, aortic pulse wave velocity (PWV), late gadolinium enhancement, serum B-type natriuretic peptide (BNP), troponin I (TnI), and the impact of treatment on QOL before, and 1, 3, and 6 months after receipt of Anth-bC.
Participants averaged 50±2 (range 19–80) years in age, 58% were women, 17% were black, and they each received a range of 50 to 375 mg/m2 of doxorubicin equivalent chemotherapy. Left ventricular end systolic volume (LVESV; 48±3 to 54±3 ml; p=0.02), left ventricular strain (−17.7±0.4 to −15.1±0.4; p=0.0003), PWV (6.7±0.5 to 10.1±1 m/sec; p=0.0006), and QOL deterioration (15.4±3.3 to 28.5±3.9; p=0.008) increased, while LVEF (58±1 to 53±1%; p=0.0002) decreased within 6 months after low to moderate doses of Anth-bC. All findings persisted after accounting for age, gender, race (white/black), doxorubicin equivalent dose, doxorubicin administration technique, comorbidities associated with CV events, and cancer diagnosis (p=0.02 to 0.0001 for all). There were no new late gadolinium enhancement findings after 6 months.
Low to moderate doses of Anth-bC are associated with the early development of subclinical abnormalities of cardiac and vascular function that in other populations are associated with the future occurrence of CV events.
Cardio-oncology; chemotherapy; cardiotoxicity
Increased intraperitoneal (IP) fat is associated with increased cardiovascular (CV) risk, but mechanisms for this increase in risk are not completely established. We performed this study to assess whether IP fat is associated with ascending aortic wall thickness (AOWT), a risk factor for CV events. Four hundred and forty-one consecutive participants, aged 55–85 years, with risk factors for CV events underwent magnetic resonance measures of AOWT and abdominal fat (subcutaneous (SC) fat + IP fat). For the ascending aorta, mean wall thickness of the 4th quartile of the IP fat was higher relative to the 1st quartile (P ≤ 0.001). This difference persisted after accounting for SC fat (P ≤ 0.001), as well as age, gender, height, weight, smoking, diabetes, hypertension, low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), and C-reactive protein (CRP) (P < 0.03). Elevated IP fat volume is associated with an increase in ascending AOWT, a condition that promotes CV events in middle aged and elderly adults.
During adrenergic stress, the influence of age on left atrial (LA) function is unknown. We hypothesized that aging decreases LA total emptying fraction (LAEF) during maximal adrenergic stress. The aim of the study was to determine the influence of aging on LA function during adrenergic stress in middle aged and older patients.
We enrolled 167 middle aged and elderly participants, and measured LA and left ventricular (LV) volumes using a multi-slice three-dimensional cine white blood cardiovascular magnetic resonance (CMR) technique before and during intravenous dobutamine infused to achieve 80% of the maximum heart rate response for age. Paired sample t-test was used to detect differences in LA and LV volumes between baseline and peak dose stage of dobutamine stress CMR, and multivariable linear regression was used to identify predictors of LA function.
Participants averaged 68 ± 8 years in age, 53% were men, 25% exhibited coronary artery disease, 35% had diabetes, 9% had a remote history of atrial fibrillation, 90% had hypertension, and 11% had inducible LV wall motion abnormalities indicative of ischemia during dobutamine CMR. Increasing age correlated with LA volumes (maximal and minimal) and inversely correlated with LAEF at rest and after peak adrenergic stress. Age was an independent predictor of LAEF during adrenergic stress, even after accounting for gender, LV volumes, and other co-morbidities including inducible ischemia.
Age is associated with a decrease in LA function during adrenergic stress even after adjusting for co-morbidities associated with cardiovascular disease and LV function.
aging; left atrial function; adrenergic stress; cardiac MRI
Over the past decade, cardiovascular magnetic resonance (CMR) has evolved into a cardiac stress testing modality that can be used to diagnose myocardial ischemia using intravenous dobutamine or vasodilator perfusion agents such as adenosine or dipyridamole. Because CMR produces high-resolution tomographic images of the human heart in multiple imaging planes, it has become a highly attractive noninvasive testing modality for those suspected of having myocardial ischemia. The purpose of this article is to review the clinical, diagnostic, and prognostic utility of stress CMR testing for patients with (or suspected of having) coronary artery disease.
stress CMR; dobutamine; adenosine; myocardial ischemia
To assess the utility of dobutamine cardiovascular magnetic resonance (DCMR) results for predicting cardiac events in individuals with reduced left ventricular ejection fraction (LVEF).
It is unknown whether DCMR results identify a poor cardiac prognosis when the resting LVEF is moderately to severely reduced.
Two-hundred consecutive patients aged 30 to 88 (average 64) years with a LVEF ≤55% that were poorly suited for stress echocardiography, underwent DCMR in which LV wall motion score index (WMSI), defined as the average wall motion of the number of segments scored, was assessed at rest, during low dose, and after peak intravenous infusion of dobutamine/atropine. All participants were followed for an average of 5 years after DCMR to ascertain the post testing occurrence of cardiac death, myocardial infarction (MI), and unstable angina or congestive heart failure warranting hospitalization.
After accounting for risk factors associated with coronary arteriosclerosis and MI, a stress induced increase in WMSI during DCMR was associated with future cardiac events (p< 0.001). After accounting for resting LVEF, a DCMR stress induced change in WMSI added significantly to predicting future cardiac events (p=0.003), but this predictive value was confined primarily to those with a LVEF >40%.
In individuals with mild to moderate reductions in LVEF (40% to 55%), dobutamine induced increases in WMSI forecast MI and cardiac death to a greater extent than an assessment of resting LVEF. In those with a LVEF < 40%, a dobutamine induced increase in WMSI does not predict MI and cardiac death beyond the assessment of resting LVEF.
magnetic resonance imaging; cardiac prognosis; myocardial ischemia; dobutamine stress imaging
During cardiovascular stress, if right ventricular (RV) exceeds left ventricular (LV) stroke volume, then a large volume of blood is displaced into the pulmonary circulation that may precipitate pulmonary edema. We sought to determine the metrics by which cardiovascular magnetic resonance (CMR) could measure simultaneous displacement of right and LV stroke volume during dobutamine stress.
Thirteen healthy subjects (5 women) aged 53±10 years without medical conditions and taking no medications underwent 2 CMR exams at 1.5 T separated by 4 to 8 weeks in which right and LV stroke volume were determined during intravenous dobutamine and atropine infused to achieve 80% of the maximum predicted heart rate response (MPHRR) for age.
The right and LV stroke volume were highly correlated at each level of stress (rest, r=0.98, p=0.007; low stress, r=0.87, p=0.001; and peak stress, r=0.88, p=0.001), and the mean difference in SV at each level of stress (rest, low stress, and peak stress was 0 to 2 ml on both exam 1 and 2.
Simultaneous change in right and left ventricular stroke volume can be assessed in a highly reproducible manner throughout the course of dobutamine CMR stress administered to achieve 80% of MPHRR for age. This technology may help identify discrepancies in right and LV stroke volume during cardiovascular stress that are associated with the development of pulmonary edema.
Fat in the renal sinus (RS), a region of the kidney in which low pressure venous and lymphatic vessels are present, may indirectly influence blood pressure (BP). The purpose of this study was to assess the association between RS fat and control of BP upon receipt of antihypertensive medications.
Two hundred-five (205) participants aged 55 to 85 years at risk for cardiovascular (CV) events underwent magnetic resonance imaging assessments of abdominal and RS fat, measurement of blood pressure, and determination of the number of prescribed antihypertensive medications. Multivariable linear regression was used to determine associations between RS fat, blood pressure, and the number of prescribed antihypertensive medications.
Abdominal fat averaged (416 ± 160 cm3, median and interquartile range (IQR) of 396 cm3 and 308 to 518 cm3); intraperitoneal (IP) fat averaged (141 ± 73 cm3, median and IQR of 129 cm3 and 86 to 194 cm3); and RS fat averaged (4.6 ± 3.2 cm3, median and IQR of 4.2 cm3 and 2.2 to 6.6 cm3). After accounting for age, gender, height, body mass index (BMI), and IP fat, RS fat correlated with the number of prescribed antihypertensive medications (p=0.010), stage II hypertension (p=0.02), and renal size (p=<0.001).
In conclusion, after accounting for other body fat depots and risk factors for hypertension, renal sinus fat volume is associated with the number of prescribed antihypertensive medications and stage II hypertension. These results indicate that further studies are warranted to determine if fat accumulation in the renal sinus promotes hypertension.
Renal sinus; intraperitoneal fat; hypertension; blood pressure; body mass index
coronary artery disease; cardiovascular magnetic resonance; adverse cardiac prognosis; cardiovascular computer tomography
To determine if dobutamine induced abnormal stress induce changes in left ventricular (LV) stroke volume (SV) and aortic stiffness predict future pulmonary edema.
Heightened aortic stiffness that reduces LV stroke volume during adrenergic stress may serve as a marker for future pulmonary edema (P edema).
We measured LVSV, ventriculo-vascular stiffness (pulse pressure/LVSVi), and aortic distensibility (AoD) at rest and during intravenous dobutamine using cardiovascular magnetic resonance (DCMR). Personnel blinded to DCMR followed participants longitudinally over time to identify those admitted to the hospital with P edema. Data from 44 participants who experienced a hospital admission for P edema were compared to data from 72 participants of similar age, gender, and resting LV ejection fraction who remained free of P edema.
Expressed as median and interquartile range, participants with versus without P edema exhibited a reduced ratio of stress/rest LVSV (0.9 [0.7,1.1] versus 1.0 [0.9,1.2], respectively, p= 0.002); an increased ventriculo-vascular stiffness stress/rest ratio (1.4 [1.0,1.6] versus 1.0 [0.8,1.3], respectively, p= ≤ 0.001); and a reduced stress induced measure of AoD (0.8 [0.3,1.3] versus 1.6 [1.2,3.2] mmHg−3, respectively, p=0.002). After accounting for age, gender, LVEF, risk factors for P edema and the presence of dobutamine induced ischemia, LVSV reserve and the stress/rest ventriculo-vascular stiffness ratio remained different (p<0.008 for both) between those with and without P edema.
In patients without inducible ischemia during dobutamine stress, in whom one might otherwise assume a favorable prognosis, the failure to increase LV stroke volume, or an increase in ventriculo-vascular stiffness indicates patients at risk for subsequent P edema.
Stroke volume; heart failure; dobutamine cardiovascular magnetic resonance
To determine if cardiovascular magnetic resonance (CMR) measures of gadolinium (Gd) signal intensity (SI) within the left ventricular (LV) myocardium are associated with future changes in LV ejection fraction (LVEF) after receipt of doxorubicin (DOX).
Methods and Results
Forty Sprague-Dawley rats were divided into 3 groups scheduled to receive weekly intravenous doses of: normal saline (NS) (n=7), 1.5 mg/kg DOX (n=19), or 2.5 mg/kg DOX (n=14). MR determinations of LVEF and myocardial Gd-SI were performed before and then at 2, 4, 7, and 10 weeks after DOX initiation. During treatment, animals were sacrificed at different time points so that histopathological assessments of the LV myocardium could be obtained. Within group analyses were performed to examine time-dependent relationships between Gd-SI and primary events (a deterioration in LVEF or an unanticipated death). Six of 19 animals receiving 1.5 mg/kg of DOX and 10/14 animals receiving 2.5 mg/kg of DOX experienced a primary event; no NS animals experienced a primary event. In animals with a primary event, histopathological evidence of myocellular vacuolization occurred (p=0.04), and the Gd-SI was elevated relative to baseline at the time of the event (p<0.0001) and during the measurement period prior to the event (p=0.0001). In all animals (including NS) without an event, measures of Gd-SI did not differ from baseline.
After DOX, low serial measures of Gd-SI predict an absence of a LVEF drop or unanticipated death. An increase in Gd-SI after DOX forecasts a subsequent drop in LVEF as well as histopathologic evidence of intracellular vacuolization consistent with DOX cardiotoxicity.
cardiotoxicity; chemotherapy; congestive heart failure; doxorubicin
This study was performed to determine the utility of dobutamine stress test results for predicting myocardial infarction (MI) and cardiac death in patients with chest pain and left ventricular hypertrophy (LVH).
Methods and Results
Three hundred fifty-three (353) participants, aged 64±12 years (54% men) underwent dobutamine cardiovascular magnetic resonance (DCMR) stress testing and then were followed for 6±2 (range 0.5 to 11.5) years to assess the post-DCMR occurrence of MI or cardiac death. Left ventricular mass and the presence or absence of ischemia were determined; LVH was defined as > 96 g/m2 in men and > 77 g/m2 in women. LVH was present in 62 participants (18 % of the men and 17% of the women, p=0.90). Seventy-one (20%) participants experienced a MI or cardiac death during follow-up. The MI and cardiac death rate was more frequent in those with versus without LVH (32% vs. 17%, p=0.009). In multivariable analysis that accounted for the presence of pre-existing coronary artery disease, hypertension, diabetes, stress induced ischemia, and reduced LVEF, LVH was an independent predictor of MI and cardiac death (hazard ratio = 1.99, 95% confidence interval = 1.13-3.50; p=0.02).
Left ventricular hypertrophy is predictive of future MI and cardiac death in patients with or without inducible ischemia during dobutamine cardiac stress testing. As a result, LVH should be reported in those referred for dobutamine cardiac stress tests, particularly those without inducible ischemia, in whom otherwise one would assume a favorable cardiac prognosis.
hypertrophy; magnetic resonance imaging; myocardial infarction
Cancer survivors exposed to anthracyclines experience an increased risk of cardiovascular (CV) events. We hypothesized that anthracycline use may increase aortic stiffness, a known predictor of CV events.
Patients and Methods
We performed a prospective, case-control study involving 53 patients: 40 individuals who received an anthracycline for the treatment of breast cancer, lymphoma, or leukemia (cases), and 13 age- and sex-matched controls. Each participant underwent phase-contrast cardiovascular magnetic resonance measures of pulse wave velocity (PWV) and aortic distensibility (AoD) in the thoracic aorta at baseline, and 4 months after initiation of chemotherapy. Four one-way analyses of covariance models were fit in which factors known to influence thoracic aortic stiffness were included as covariates in the models.
At the 4-month follow-up visit, aortic stiffness remained similar to baseline in the control participants. However, in the participants receiving anthracyclines, aortic stiffness increased markedly (relative to baseline), as evidenced by a decrease in AoD (P < .0001) and an increase in PWV (P < .0001). These changes in aortic stiffness persisted after accounting for age, sex, cardiac output, administered cardioactive medications, and underlying clinical conditions known to influence aortic stiffness, such as hypertension or diabetes (P < .0001).
A significant increase in aortic stiffness occurs within 4 months of exposure to an anthracycline which was not seen in an untreated control group. These results indicate that previously regarded cardiotoxic cancer therapy adversely increases thoracic aortic stiffness, a known independent predictor of adverse cardiovascular events.
To determine the effect of statins and hormone replacement therapy on submaximal exercise induced coronary artery blood flow in postmenopausal women without a history of coronary artery disease.
Hormone replacement or statin therapy in early postmenopausal women without coronary artery disease have been shown to enhance arterial endothelial function; we hypothesized that these agents would improve submaximal exercise induced coronary artery blood flow.
Sixty-four postmenopausal women, aged 50–65 years without documented coronary artery disease, were randomized in a double blinded, cross-over fashion to receive 8 weeks of hormone replacement therapy versus placebo, with or without 80 mg/day of atorvastatin. Prior to receipt of any therapy and after each treatment period, each woman underwent measures of coronary artery blood flow at rest and stress.
The combination of hormone replacement therapy and atorvastatin increased submaximal exercise induced coronary artery blood flow (p=0.04). In the subgroups of women compliant with treatment, resting coronary artery blood flow increased in those receiving hormone replacement therapy (p=0.03) or statin therapy (p=0.02).
In postmenopausal women aged 50–65 years without documented coronary artery disease, rest and submaximal exercise induced coronary artery blood flow improve after receipt of high dose atorvastatin and conjugated estrogen therapy.
estrogen; statins; exercise; magnetic resonance imaging; coronary artery flow
To determine the prognostic utility of dobutamine cardiovascular magnetic resonance (DCMR) stress test results in women.
To date, the preponderance of studies reporting the utility of DCMR stress results for predicting cardiac prognosis have been performed in men. We sought to determine the utility of DCMR results for predicting cardiac prognosis in women.
Two hundred sixty-six consecutively referred women underwent DCMR in which left ventricular wall motion (LVWM) was assessed at rest and after intravenous dobutamine and atropine. Inducible LVWM abnormalities were identified during testing. Women were contacted to determine the post DCMR occurrence of a cardiac event. All events were substantiated according to defined criteria, and then verified after a thorough medical record review by individuals blinded to testing data.
Women were contacted an average of 6.2 ± 1.6 (median 6.2, range 0.8 to 10.4) years after DCMR; 27% of the women experienced an inducible LVWM abnormality during testing. In those with and without inducible LVWM abnormalities, the proportion of women with cardiac events were 63% versus 30%, respectively, (hazard ratio [HR] of 2.7 [CI 1.8 – 4.3] for the presence of inducible LVWM abnormalities p<0.0001). The proportion of women with myocardial infarction (MI) and cardiac death were 33.3% and 7.5%, respectively. This resulted in a HR for MI and cardiac death of 4.1 [CI 2.2 – 9.4] for those with versus without inducible LVWM abnormalities; p<0.0001. A subgroup analysis was performed in women without a history of coronary artery disease and in those with LVWM abnormalities, DCMR remained an adverse predictor of cardiac events (HR 4.0, CI 1.8 – 9.0, p=0.003).
Inducible LVWM abnormalities during DCMR predict cardiac death and MI in women. Similar to men, these results indicate DCMR is a valuable noninvasive stress imaging modality for identifying cardiac risk in women with known or suspected ischemic heart disease.
Women; Prognosis; Magnetic Resonance
To determine myocardial infarct (MI) size during cardiovascular magnetic resonance (CMR) at 1.5 Tesla using 0.1 mmol/kg bodyweight of gadobenate dimeglumine (Gd-BOPTA) and 0.2 mmol/kg bodyweight of gadopentetate dimeglumine (Gd-DTPA).
Twenty participants (16 men, 4 women), aged 58 ± 12 years, with a prior chronic MI were imaged in a cross-over design. Participants received 0.2 mmol/kg bodyweight of Gd-DTPA, and 0.1 mmol/kg bodyweight of Gd-BOPTA on 2 occasions separated by 3 to 7 days
The correlations were high between Gd-DTPA and Gd-BOPTA measures of infarct volume (r=0.93) and the percentage of infarct relative to LV myocardial volume (r=0.85). The size and location of the infarcts were similar (p=0.9) for the 2 contrast agents. Interobserver correlation of infarct volume (r=0.91) was high.
In chronic myocardial infarction, late gadolinium enhancement identified with a single 0.1 mmol/kg bodyweight dose of Gd-BOPTA is associated in volume and location to a double (0.2 mmol/kg body weight) dose of Gd-DTPA. Lower doses of higher relaxivity contrast agents should be considered for determining LV myocardial infarct size.
myocardial infarction; contrast; ischemic heart disease
To determine whether middle-aged and older individuals with impaired fasting glucose (IFG), but no clinical evidence of cardiovascular disease, exhibit abnormal changes in proximal thoracic aortic stiffness or left ventricular (LV) mass when compared with healthy counterparts.
RESEARCH DESIGN AND METHODS
From the Multi-Ethnic Study of Atherosclerosis, 2,240 subjects with normal fasting glucose (NFG), 845 with IFG, and 414 with diabetes, all aged 45 to 85 years and without preexisting coronary artery disease, underwent MRI determinations of total arterial and proximal thoracic aortic stiffness and LV mass. The presence or absence of other factors known to influence arterial stiffness was assessed.
After adjustment for clinical factors known to modify arterial stiffness, proximal thoracic aortic stiffness was not increased in those with IFG compared with those with NFG (1.90 ± 0.05 versus 1.91 ± 0.04 10−3 mmHg−1, respectively, P = 0.83). After accounting for clinical factors known to influence LV mass, LV mass was increased in those with diabetes relative to those with NFG (150.6 ± 1.4 versus 145.8 ± 0.81 g, P < 0.0009) but not in those with IFG in comparison with NFG (145.2 ± 1.03 versus 145.8 ± 0.81 g, P = 0.56).
Middle-aged and older individuals with the pre-diabetes state of IFG do not exhibit abnormal proximal thoracic distensibility or LV hypertrophy relative to individuals with NFG. For this reason, an opportunity may exist in those with IFG to prevent LV hypertrophy and abnormal aortic stiffness that is observed in middle-aged and older individuals with diabetes.
Fat accumulation around the heart and aorta may impact cardiovascular (CV) health. The purpose of this study was to conduct a systematic investigation to examine potential associations of these fat depots with risk factors for CV events, which has not been done before.
Pericardial fat, periaortic fat around the ascending aorta (AA), descending aorta (DA) and aortic arch, and abdominal subcutaneous and visceral fat were measured by MRI in older adults with (n=385, 69±8 years, 52% female) and without (n=50, 69±8 years, 58% female) risk factors for a CV event.
Individuals with CV risk factors exhibited greater fat volumes across all fat depots compared to those without risk factors. In analysis of covariance accounting for age, gender, race/ethnicity, diabetes, hypertension, coronary artery disease, smoking, and BMI, individuals with risk factors possessed higher epicardial, pericardial, AA, DA, and abdominal visceral fat (p<0.05). When matched one-to-one on age, gender, race/ethnicity, and BMI, AA and DA fat were higher in those with versus without CV risk factors (p<0.01).
Older adults with a high risk for CV events have greater periaortic fat than low-risk adults, even after accounting for BMI. More studies are needed to determine whether greater periaortic fat predicts future CV events.
pericardial fat; periaortic fat; aging; cardiovascular risk
The distinction between normal right ventricular (RV) trabeculations from abnormal has been difficult. We evaluated whether RV volume and function are related to left ventricular (LV) noncompaction (NC) cardiomyopathy and clinical events. Trabeculations/possible LVNC by cardiac magnetic resonance imaging (cMRI) was retrospectively observed among 105 consecutive cases. We measured LV end-systolic (ES) noncompacted:compacted ratio, RV ejection fraction (EF), RV apical trabecular thickness, and RV end-diastolic (ED) noncompacted:compacted ratio. A control group of 40 subjects was also reviewed to assess the exploratory measures. Comparing those with LV ES noncompacted:compacted ratio ≥ 2, < 2, and the normal control group, adjusted means for RV apical trabecular thickness and RV ED noncompacted:compacted ratio were generated. Logistic regression was used to evaluate the association of composite events traditionally associated with LV NC with RV EF after adjustment for above covariates, cardiovascular risk factors, delayed enhancement, LV EF, and LV ES noncompacted:compacted ratio. Analysis of RV morphology found greater apical trabecular thickness among those with LV ES noncompacted:compacted ratio ≥ 2 as compared with LV ES noncompacted:compacted ratio < 2 or normal control group (31 ± 5 mm vs. 27 ± 2.6 mm vs. 22 ± 4 mm; p = 0.03 and p = 0.003, respectively). There was no difference between the groups in relation to the RV end-diastolic (ED) noncompacted:compacted ratio . Low RV EF and LV ES noncompacted:compacted ratio ≥ 2 had significant association with clinical events in this population even after adjusting for clinical and imaging parameters (p = 0.04 and p < 0.001, respectively). In conclusion, RV dysfunction in a morphologic LVNC population is strongly associated with adverse clinical events. LVNC is associated with increased trabeculations of the RV apex.
Noncompaction; Right Ventricle; Heart Failure
Tagged cardiac magnetic resonance (CMR) provides detailed information on regional myocardial function and mechanical behavior. T1 mapping by CMR allows non-invasive quantification of myocardial extracellular expansion (ECE) which has been related to interstitial fibrosis in previous clinical and sub-clinical studies. We assessed gender associated differences in the relation of ECE to LV remodeling and myocardial systolic and diastolic deformation in a large community based multi-ethnic population.
Methods and Results
Mid-ventricular mid-wall peak circumferential shortening and early diastolic strain rate (EDSR); LV torsion and torsional recoil rate were determined using CMR tagging. Mid ventricular short axis T1 maps were acquired in the same examination pre and post-contrast injection using Modified Look-Locker Inversion Recovery sequence (MOLLI). Multivariable linear regression (B= estimated regression coefficient) was used to adjust for risk factors and sub-clinical disease measures. Of 1230 participants, 114 participants had visible myocardial scar by late gadolinium enhancement. Participants without visible myocardial scar (n=1116) had no previous history of clinical events. In the latter group, multivariable linear regression demonstrated that lower post-contrast T1 times, reflecting greater ECE were associated with lower circumferential shortening (B=−0.1, p=0.0001), lower end diastolic volume index (LVEDVi) (B=0.6, p=0.0001) and lower LV end diastolic mass index (LVMi) (B=0.4, p=0.0001). In addition, lower post-contrast T1 times were associated with lower EDSR (B=0.01, p=0.03) in women only; and lower LV torsion (B=0.005, p=0.03) a lower LV ejection fraction (B=0.2, p=0.01) in men only.
Greater ECE is associated with reduced LVEDVi and LVMi in a large multi-ethnic population without history of previous cardiovascular events. In addition, greater ECE is associated with reduced circumferential shortening, lower EDSR, and a preserved ejection fraction in women; while in men, greater ECE is associated with greater LV dysfunction manifested as reduced circumferential shortening, reduced LV Torsion and reduced ejection fraction.
interstitial myocardial fibrosis; circumferential strain; LV torsion; T1 mapping; tagging