BALLO, PIERCARLO, ANDREA MOTTO, SERGIO MONDILLO, AND SERGIO A. FARAGUTI. Impact of obesity on left ventricular mass and function in subjects with chronic volume overload. Obesity. 2007;15: 2019 -2026. Objective: Previous studies evaluated the effect of obesity on left ventricular (LV) mass and systolic function in healthy subjects and in patients with coexistent chronic LV pressure overload due to hypertension, but no data exist regarding subjects with underlying volume overload. This study assessed the impact of overweight-obesity on LV mass and systolic function in patients with coexistent chronic LV volume overload. Research Methods and Procedures:In 885 subjects with degenerative aortic regurgitation, a common cause of LV volume overload, LV mass, ejection fraction, and myocardial contractility were determined by echocardiography. Results: LV mass was greater in overweight (193.5 Ϯ 54.2 g) and further increased in obese subjects (208.4 Ϯ 63.6 g) in comparison with normal-weight patients (177.7 Ϯ 54.9 g) (p Ͻ 0.0001), and these differences were still evident after adjustment for LV workload, gender, and body size. Despite no differences in ejection fraction, LV myocardial contractility was lower in overweight (92.6 Ϯ 14.8%) and obese subjects (91.7 Ϯ 14.4%) than normalweight individuals (95.6 Ϯ 16.0%) (p ϭ 0.0058). The magnitudes of these effects were not different from those found in age-, gender-, and body size-matched controls, suggesting additive interaction, rather than synergistic, between overweight-obesity and the underlying condition of volume overload. Multivariate analysis showed that BMI independently predicted LV mass and that the negative effect on LV myocardial contractility was mediated by LV hypertrophy. Discussion: Overweight and obesity are associated with LV hypertrophy and contractile impairment in patients with underlying chronic LV volume overload.

Aims To analyse whether heart rate may affect the efficacy of adenosine, verapamil and carotid sinus massage in terminating symptomatic episodes of paroxysmal supraventricular tachycardia (PSVT) in adults. Methods and results The study population was selected among 175 adult patients, affected by symptomatic PSVT. One hundred and six of them were considered eligible for the study. Each subject received one of the following treatments: verapamil, 5 mg intravenously (IV) in 5-10 min, followed by 1-5 lg/kg/min; adenosine, 6 mg IV, followed by 12 mg IV after 2-3 min; carotid sinus massage. Adenosine and verapamil were similarly effective in terminating PSVT (74.4% vs 81.8%, P ¼ 0:45). The efficacy of carotid sinus massage was significantly lower in comparison with the other two groups (32.4%, P ¼ 0:00032 vs adenosine and P ¼ 0:000044 vs verapamil group). At logistic regression, PSVT rate showed a positive association with the percentage of sinus rhythm restoration in the group who received adenosine (P ¼ 0:0004). The probability of success in resolving the tachycardia following treatment with adenosine was >75% for heart rates over 166 beats per minute (bpm), but rapidly decreased at lower frequencies, reducing to 25% at 138 bpm. In the verapamil group, PSVT rate was negatively related to the percentage of sinus rhythm restoration (P ¼ 0:018). The probability of success in terminating PSVT following administration of verapamil was >75% for heart rates lower than 186 bpm, but tended to decrease at faster rates, reducing to 25% at 241 bpm. No significant effects of heart rate were observed in the carotid sinus massage group (P ¼ 0:17). The probability curves obtained in the adenosine and verapamil group crossed at a point corresponding to 173 bpm, which may represent a cut-off value to predict which treatment could ensure higher rate of success. Conclusions Heart rate predicts restoration of sinus rhythm in adult subjects with symptomatic episodes of PSVT treated with adenosine and verapamil. Adenosine is highly effective in PSVT characterised by fast rates, whereas the efficacy of verapamil is increased in patients with low-frequency PSVT.

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