Silvia Diluzio | PubMed Health

PubMed2004

Relation between contractile reserve and improvement in left ventricular function with beta-blocker therapy in patients with heart failure secondary to ischemic or idiopathic dilated cardiomyopathy.

Beta blockers improve left ventricular (LV) ejection fraction but patient responses are heterogenous. We investigated the role of contractile reserve (CR) in predicting beta-blocker response in ischemic and nonischemic cardiomyopathy. Resting and low-dose dobutamine echocardiograms were recorded in 32 patients with heart failure (LV ejection fraction <or=35%), 18 with ischemic cardiomyopathy (IC), and 14 with idiopathic dilated cardiomyopathy (IDC). A segment was defined as CR positive (CR+) or negative (CR-) based on response to dobutamine. Patients were then classified as CR+ or CR- based on number of improved segments (IC group) or ejection fraction improvement (IDC group) in response to dobutamine. During follow-up (2, 6, and 14 months after beta-blocker initiation), response was measured by the percent of segments showing improved contractility from baseline, ejection fraction, and wall motion score index. In the IC group, the percent of improved segments was greater at 2 and 6 months in CR+ versus CR- (70% vs 15% and 39% vs 17%, p <0.05), whereas it was greater at all periods in the patients with IDC (36% vs 9% at 2 months, 50% vs 19% at 6 months, and 63% vs 42% at 14 months, p <0.05). Findings for ejection fraction and wall motion score index were similar. Therefore, time course and magnitude of improvement in LV function in patients with heart failure receiving beta blockers are related to CR status. CR predicts a greater early response in IC, whereas it predicts a greater response at all time periods in IDC. However, even patients without CR showed improvement in LV function at 14 months.

Adrenergic beta-Antagonists↗

PubMed2002

Evaluation of valvular regurgitation severity using digital acquisition of echocardiographic images.

BACKGROUND: Digital acquisition is a technique for storing echocardiographic data that offers advantages over conventional videotape (VT); however, limited information is available on its accuracy for the evaluation of valvular regurgitation. METHODS: We evaluated 102 patients with at least 1 regurgitant lesion. Data were obtained on VT and in 1 cardiac cycle stored digitally (1C). To assess for incremental improvement with acquisition of multiple cycles, digital images were also acquired with 2 (2C) or 3 cardiac cycles (3C). Both digital and VT images were graded for regurgitant severity as absent, trivial, mild, moderate, or severe. Kappa statistics were used to assess agreement. RESULTS: A total of 171 valvular regurgitant lesions (mild or greater) were evaluated. The overall agreement between 1C and VT images was kappa = 0.61. With multiple cycle acquisition, there was no improvement in agreement (kappa = 0.56 and 0.57 for 2C and 3C, respectively). When subgrouped, the level of agreement between 1C and VT was slightly lower for the aortic valve than for the mitral or tricuspid valves (kappa = 0.49, 0.63, 0.64, respectively). CONCLUSION: The 1C technique has substantial agreement and correlation with standard VT for the evaluation of regurgitant lesions with the use of color flow Doppler. The acquisition of multiple cardiac cycles does not provide incremental improvement over single beat acquisition.

Echocardiography, Doppler, Color↗