Right ventricular function measured by TAPSE in obese subjects at the time of acute myocardial infarction and 2year outcomes.

INTRODUCTION: Obesity is associated with significantly better outcome after acute myocardial infarction (AMI), a phenomenon known as 'obesity paradox'. Tricuspid annular plane systolic excursion (TAPSE) is an echocardiographic measurement of right ventricular (RV) function and has prognostic implications at the time of AMI. METHODS: We examined the difference in RV function among patients admitted with AMI according to obesity status. In a single center cohort analysis of 105 patients admitted between 2010 and 2011 with the diagnosis of AMI. Demographic, anthropometric data and cardiovascular risk factors were prospectively collected. All subjects had echocardiogram within 48h of AMI diagnosis for TAPSE calculations. Subjects were divided into two groups based on their obesity status. RESULTS: Obese subjects had better RV function compared to non-obese, TAPSE: 19±6.6 vs. 16±4.9mm; p 0.02 at the time of AMI. There was no significant difference in TAPSE between OSA and non-OSA subjects, 19±6.3 vs. 17±6.2mm; p 0.21. After 2years of follow up, patients with obesity and better RV function were less likely to develop new onset heart failure (HF) with OR 0.30 (95% CI 0.09-0.93; p 0.03) and OR 0.31 (95% CI 0.11-0.76; p 0.007) respectively. CONCLUSION: Obese patients had better RV function measured by TAPSE at the time AMI when compared non-obese patients. Patients with better RV function at the time of AMI were less likely to develop new-onset HF and there was a trend in the obese group to less likely develop new-onset HF after 2year follow up.

Dynamic cycling in atrial size and flow during obstructive apnoea.

OBJECTIVE: Obstructive sleep apnoea (OSA) is strongly associated with cardiovascular disease. However, acute cardiovascular effects of repetitive airway obstruction are poorly understood. While past research used a sustained Mueller manoeuver to simulate OSA we employed a series of gasping efforts to better simulate true obstructive apnoeas. This report describes acute changes in cardiac anatomy and flow related to sudden changes in intrathoracic pressure. METHODS AND RESULTS: 26 healthy, normal weight participants performed 5-6 gasping efforts (target intrathoracic pressure -40 mm Hg) while undergoing Doppler echocardiography. 14 participants had sufficient echocardiographic images to allow comparison of atrial areas during the manoeuver with baseline measurements. Mitral and tricuspid E-wave and A-wave velocities postmanoeuver were compared with baseline in all participants. Average atrial areas changed little during the manoeuver, but variance in both atrial areas was significantly greater than baseline. Further, an inverse relationship was noted with left atrial collapse and right atrial enlargement at onset of inspiratory effort. Significant inverse changes were noted in Doppler flow when comparing the first beat postmanoeuver (pMM1) with baseline. Mitral E-wave velocity increased 9.1 cm/s while tricuspid E-wave velocity decreased 7.0 cm/s; by the eighth beat postmanoeuver (pMM8) values were not different from baseline. Mitral and tricuspid A-wave velocities were not different from baseline at pMM1, but both were significantly higher by pMM8. CONCLUSIONS: Repetitive obstructive apnoeas produce dynamic, inverse changes in atrial size and Doppler flow across the atrioventricular valves. These observations have important implications for understanding the pathophysiology of OSA.

Association between QRS duration and obstructive sleep apnea.

BACKGROUND: Both obstructive sleep apnea (OSA) and prolonged QRS duration are associated with hypertension, heart failure, and sudden cardiac death. However, possible links between QRS duration and OSA have not been explored. METHODS: Cross-sectional study of 221 patients who underwent polysomnography at our center. Demographics, cardiovascular risk factors and ECG were collected to explore a relationship between OSA and QRS duration. RESULTS: The apnea-hypopnea index (AHI) was positively correlated with QRS duration (r = 0.141, p = 0.03). Patients were divided into 3 groups: AHI < 5 (61), AHI 5-29 (104), and AHI > 30 (55). The mean QRS duration prolonged significantly as OSA worsened (AHI < 5, 85 ± 9.5; AHI 5-29, 89 ± 11.9; and AHI > 30, 95 ± 19.9 ms, p = 0.001). QRS ≥ 100 ms was present in 12.7% of patients with severe OSA compared with 0% in the rest of the sample (p < 0.0001). After adjustment for age, race, and cardiovascular risk factors, this association remained significant in women but not in men. CONCLUSION: QRS duration and OSA were significantly associated. Severity of OSA independently predicted prolonged QRS in women but not men. Nevertheless, prolongation of QRS duration in either sex may potentiate arrhythmic risks associated with OSA.

Impact of obesity on total and cardiovascular mortality--fat or fiction?

Obesity is an excessive accumulation of fat that can impair health. Because the direct measurement of body fat is difficult to perform, a number of anthropometric measures have been employed as surrogates, of which BMI is the most commonly used. However, its usefulness has been questioned as a BMI in the overweight and mildly obese range is associated with improved survival and fewer cardiovascular events than a BMI in the normal range, a phenomenon known as the 'obesity paradox'. Waist circumference, waist-to-hip ratio, and waist-to-height ratio take into consideration body-fat distribution, especially abdominal obesity, and seem to predict cardiovascular risk better than does BMI.

Measuring health related quality of life in coronary heart disease: the importance of feeling well.

Health related quality of life (HRQoL) is used increasingly as a measure of the outcome of CHD. As an improvement in survival of CHD continues, assessment of HRQoL has become an important and useful outcome measure complementing the traditional "hard outcomes" such as mortality for evaluating benefits of medical interventions. Increasing number of clinical trials is applying HRQoL as an outcome measure of CHD therapy. Assessment of HRQoL in CHD should comprise a disease-specific measure in addition to a generic measure. This review aims to provide an overview of generic, disease-specific, and utility measures used in the assessment of HRQoL in CHD.