No abstract

To determine whether alterations of left ventricular (LV) structure are associated with improved LV function under chronic clonidine monotherapy (300-450 g/day) of essential hypertension, 11 male patients (age range 47-61 years) were followed for 5.4 +/- 0.9 months using echocardiography and Doppler echocardiography. Blood pressure decreased from a mean of 168/105 to 150/96 mmHg (p less than 0.01), heart rate remained unchanged (73 +/- 10 vs. 71 +/- 10 beats/min). LV muscle mass decreased from 350 +/- 73 to 297 +/- 56 g (p less than 0.02), LV volume/muscle mass ratio increased from 0.58 +/- 0.13 to 0.69 +/- 0.12 ml/g (p less than 0.005). Ejection time increased from 276 +/- 17 to 296 +/- 17 ms (p less than 0.01), whereas no significant change was found for pre-ejection period, ejection fraction, cardiac index and LV dimensions. Doppler analysis revealed improved isovolumic relaxation time (116 +/- 17 vs. 84 +/- 28 ms; p less than 0.05), but no change in isovolumic contraction duration, maximal inflow velocities, time-velocity integrals and their duration, rate of acceleration and deceleration of early and atrial filling, and of their ratios. It is concluded that no reliable improvement in diastolic or systolic LV function is observed in chronic clonidine monotherapy of essential hypertension despite a normalization of blood pressure and a regression of LV hypertrophy.

The aim of this retrospective study was to evaluate the necessity of the replacement of an implantable cardioverter/defibrillator (ICD) in patients with pulse generator battery depletion without an adequate, spontaneous arrhythmia episode during the life-time of the first implanted device. In this study 213 patients with implanted ICDs were enrolled. In 62 patients an elective generator replacement due to battery depletion was performed. Both patient groups (Group A: patients with generator replacement n = 62 and Group B: patients without replacement n = 151) were not different with regard to main clinical characteristics, such as underlying heart disease and left ventricular function. In both groups there was a predominance of male patients (Group A: 89%; Group B: 83%). The mean age was 58 +/- 11 years and 59 +/- 11 years in Group A and Group B, respectively. Coronary artery disease was present in 66% and 68% of the patients. There was a comparable left ventricular ejection fraction: Group A: 30.5 +/- 9% vs Group B: 31.9 +/- 9%. The follow-up time was much longer in Group A patients compared to Group B patients (50.5 +/- 14 vs. 16.5 +/- 11 months). For the total patient group there was a 5 year event-free probability of 23%, no differences were found between both groups. The subanalysis in Group A patients revealed no difference in the probability of ICD-shock occurrence prior to or after the replacement of the pulse generator. In 48/62 (77%) of Group A patients adequate ICD discharges were documented. In 15/62 (24%) patients shock occurred before and after generator replacement. In 6/62 (10%) of Group A patients, the first adequate ICD-therapy was documented after generator replacement. The results of this study indicate the necessity of an ICD-pulse generator replacement even in patients without an adequate device discharge during the life-time of the first implanted device.