Role of ACE inhibitors in hypertension with left ventricular hypertrophy

Influence of physical exercise and sodium intake on arterial pressure and cardiac hypertrophy in rats

Evidence shows that cardiac hypertrophy (CH) is a risk factor for many cardiovascular diseases. Several stimuli may cause CH-like manifestations and promote volume or pressure overload. Exercise-induced cardiac hypertrophy is an expected adaptation to regular exercise training. Salt intake has been shown to be the most important determinant of blood pressure in different populations. The purpose of the present work was to verify the influence of physical exercise and sodium intake on the blood pressure and myocardium. The study was performed on 36 rats divided into six groups: Group I (diet without salt overload), Group II (diet without salt overload and swimming), Group III (diet with 2.5% NaCl solution and swimming), Group IV (diet with 5% NaCl solution and swimming), Group V (diet with 2.5% NaCl solution without exercise), Group VI (diet with 5% NaCl solution without exercise). The arterial pressure was significantly lower in Group I when compared with Group IV. The ratio of cardiac mass/body mass was increased in Groups III and IV. In conclusion, there was evidence that exercise training and NaCl intake promotes arterial hypertension and cardiac hypertrophy.

Fosinopril reduces left ventricular mass in untreated hypertensive patients: a controlled trial

AIMS

Left ventricular hypertrophy is a powerful predictor of cardiovascular morbidity and mortality. We tested the hypothesis that fosinopril, an angiotensin-converting enzyme inhibitor, reduces left ventricular mass in hypertensive patients.

METHODS

Thirty-three patients with untreated mild essential hypertension were randomised to treatment with oral fosinopril (10 mg-20 mg daily) or placebo for 12 weeks. The primary outcome measure was the change in left ventricular mass index determined by echocardiography.

RESULTS

Diastolic blood pressure changed from 95.5+/-2.1 mmHg at baseline to 96.6+/-2.8 mmHg at the final visit in control patients and changed from 96.6+/-2.3 mmHg to 91.5+/-3.0 mmHg in patients treated with fosinopril (P= 0.04). Systolic blood pressure changed from 147.4+/-3.2 mmHg at baseline to 152.7+/-4.4 mmHg at the final visit in control patients and changed from 157.6+/-5.1 mmHg to 149.1+/-6.1 mmHg in patients treated with fosinopril (P=0.02). Fosinopril reduced diastolic pressure by 6.3 (95%CI 0.3-12.4) mmHg and systolic pressure by 13.3 (95%CI 2.7-23.8) mmHg compared with placebo. The left ventricular mass index changed from 110.0+/-8.3 gm(-2) to 113.1+/-8.7 g m(-2) in the control patients and changed from 120.8+/-5.8 g m(-2) to 109.0+/-7.5 g m(-2) in patients treated with fosinopril (P=0.02). Fosinopril reduced left ventricular mass index by 14.9 (95%CI 2.2-27.6) g m(-2) compared with placebo. There was no significant change in the left ventricular systolic or diastolic function, nor were there any significant changes in plasma electrolytes and renal function.

CONCLUSIONS

Treatment with fosinopril for 12 weeks reduced left ventricular mass significantly in hypertensive patients.

Age-related changes in cardiac physiology. Can they be postponed or treated by drugs?

The basic mechanisms that cause aging are still poorly understood. Longitudinal prospective population studies using noninvasive examination techniques have improved our ability to differentiate between aging and disease. This review describes some general morphological and functional aging-related changes of the heart that have clinical relevance, and considers the possibility of drug treatment for the manifestations of aging per se. Digitalis has not been shown to improve the aging-related decline in myocardial strength and contractility. During aging, heart tissue stiffens and the speed and extent of diastolic filling decline. The latter is a limiting functional factor, particularly during increases in heart rate. Lowering peripheral vascular resistance, which is often increased in older people, might indirectly improve heart function. However, no drug has been shown to improve myocardial strength or lower tissue stiffness via a direct effect on the heart. It has been claimed, however, that calcium antagonists might improve diastolic filling. Morphological changes during aging are dominated by some left ventricular wall and septal hypertrophy, and left atrial and ventricular widening. Recent findings have suggested that angiotensin II might act as a growth stimulating factor, promoting cardiac hypertrophy. This has led to speculation that ACE inhibitors might contribute to the restructuring of the heart, not only in hypertension but also in patients with the common combination of slightly elevated blood pressure and aging-related myocardial hypertrophy. At present, it appears that improving exogenous factors (e.g. lifestyle, living circumstances and access to adequate medical care) offers greater opportunities for postponing cardiac aging than drugs that directly interfere with the physiological aging of the heart.