Exercise performance in patients with dilated cardiomyopathy: relationship to resting left ventricular function

Aerobic exercise intensity assessment and prescription in cardiac rehabilitation: a joint position statement of the European Association for Cardiovascular Prevention and Rehabilitation, the American Association of Cardiovascular and Pulmonary Rehabilitation and the Canadian Association of Cardiac Rehabilitation

Aerobic exercise intensity prescription is a key issue in cardiac rehabilitation, being directly linked to both the amount of improvement in exercise capacity and the risk of adverse events during exercise. This joint position statement aims to provide professionals with up-to-date information regarding the identification of different exercise intensity domains, the methods of direct and indirect determination of exercise intensity for both continuous and interval aerobic training, the effects of the use of different exercise protocols on exercise intensity prescription and the indications for recommended exercise training prescription in specific cardiac patients' groups. The importance of functional evaluation through exercise testing prior to starting an aerobic training program is strongly emphasized, and ramp incremental cardiopulmonary exercise test, when available, is proposed as the gold standard for a physiologically comprehensive exercise intensity assessment and prescription. This may allow a shift from a 'range-based' to a 'threshold-based' aerobic exercise intensity prescription, which, combined with thorough clinical evaluation and exercise-related risk assessment, could maximize the benefits obtainable by the use of aerobic exercise training in cardiac rehabilitation.

The effect of cardiac fibrosis on left ventricular remodeling, diastolic function, and N-terminal pro-B-type natriuretic peptide levels in patients with nonischemic dilated cardiomyopathy

BACKGROUND

Cardiac fibrosis is common and associated with poor prognosis in patients with heart failure. We investigated the effect of cardiac fibrosis on the left ventricular (LV) diastolic function, functional capacity, LV remodeling, and biochemical parameters in patients with nonischemic dilated cardiomyopathy (NIDC). In addition, we investigated the biochemical and echocardiographic predictors of cardiac fibrosis in this group.

METHODS AND RESULTS

Forty patients with NIDC were enrolled. Cardiac fibrosis was evaluated according to the presence of late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging. Nineteen patients had cardiac fibrosis (Group I) and 21 patients did not have cardiac fibrosis (Group II). LV systolic and diastolic parameters were assessed with conventional and tissue Doppler echocardiography. N-terminal pro-B-type natriuretic peptide (NT-pro BNP) levels of each patient were recorded. Patients with cardiac fibrosis had impaired diastolic function, higher functional class and NT-pro BNP levels, and significant LV remodeling than the patients without cardiac fibrosis. A correlation analysis revealed that the cardiac fibrosis severity was associated with functional class, cardiac chamber sizes, NT-pro BNP levels, diastolic parameters such as E/Se. A linear regression analysis demonstrated that NT-pro BNP and E/Se were the independent predictors of cardiac fibrosis.

CONCLUSION

Cardiac fibrosis correlates with impaired LV diastolic function and functional capacity, elevated NT-proBNP levels, and adverse cardiac remodeling in patients with NIDC. Therefore, the assessment of cardiac fibrosis can be useful in the management of these patients.