Effect of beta blockade on the neurohumoral and cardiopulmonary response to dynamic exercise in cardiac transplant recipients.

Abstract

Objective-To determine the effects of a small dose of ft blocker on neurohumoral and cardiopulmonary responses after cardiac transplantation. Background-Cardiac transplant recipients have a reduced exercise capacity and abnormal cardiovascular responses to exercise. The sympathoadrenal response to exercise has been shown to be abnormal with high venous noradrenaline. The effect of ft blockade on these neurohumoral mechanisms has not been defined. Methods-10 non-rejecting cardiac transplant recipients were studied. Patients carried out graded exercise to a symptom limited maximum. Blood samples were taken during exercise. Concentrations of noradrenaline, adrenaline, and atrial natriuretic peptide and plasma renin activity were measured. The next day, the exercise and sampling procedure were repeated after an oral dose of propranolol (40 mg). Results-Patients tolerated exercise poorly after p blockade, which was reflected in the maximum workload reached. Heart rate and blood pressure were significantly higher at rest and during exercise before pl blockade. Although there was no significant difference when resting, mean (SEM) noradrenaline concentrations during peak exercise were higher after p blockade (16.2 (2) v 23-6 (2.9) nmoiIl, p = 0.001). Adrenaline concentrations at peak exercise were also greater after ft blockade

Lasting reduction of heart transplant tachycardia with ivabradine is effective and well tolerated: results of 48-month study

“…Recent multicenter, prospective, randomised and controlled trials have demonstrated a significant reduction in myocardial infarction, death from heart failure and decrease of hospitalisation rate in patients treated with ivabradine [11][12][13]. Ivabradine treatment was not associated with deterioration of blood pressure, cardiac conduction, myocardial contractility or peripheral vascular tone, thereby distinguishing it from beta blocker or calcium channel blockers [4,[14][15][16].…”

The effects of atenolol and zofenopril on plasma atrial natriuretic peptide are due to their interactions with target organ damage of essential hypertensive patients

“…18,19 A few authors have blockers in patients with heart disease, 5 hypertendescribed increased plasma ANP or ANP/ sion, 6 renal replacement therapy 7 and cardiac transpulmonary capillary wedge pressure ratios after plantation. 8 An explanation for the presence or ACE inhibition, both in hypertensive subjects and absence of a stimulatory effect of beta-blockers on cardiac patients. 20,21 In those studies in which mean plasma ANP is not readily apparent; both effects ANP levels are unmodified by ACE inhibitors, the have been reported with the same drug, 2,8 with variance of ANP is usually very large, reflecting agents sharing the same pattern of cardioselectivresponses of opposite direction (ie, increases and ity, 3,7 and in the same disease state.…”

“…8 An explanation for the presence or ACE inhibition, both in hypertensive subjects and absence of a stimulatory effect of beta-blockers on cardiac patients. 20,21 In those studies in which mean plasma ANP is not readily apparent; both effects ANP levels are unmodified by ACE inhibitors, the have been reported with the same drug, 2,8 with variance of ANP is usually very large, reflecting agents sharing the same pattern of cardioselectivresponses of opposite direction (ie, increases and ity, 3,7 and in the same disease state. 3,6 Post-exercise decreases) among the subjects studied.…”

Effect of diltiazem on exercise capacity after heart transplantation

“…Despite being recommended for rate control by ISHLT, β‐blockers effect on post‐HTx exercise capacity is controversial. Although a recent study did not find harmful results, earlier data have raised concerns against the therapeutic use of β‐blockers in HTx recipients and showed that acute β‐blockade, especially if not selective, negatively affects cardiac performance and reduces exercise capacity after HTx secondary to abnormal sympathoadrenal response . This detrimental effect of β‐blockade on exercise capacity was more pronounced in patients with re‐innervated than deinnervated transplanted hearts .…”

“…Nondihydropyridine calcium channel blockers and β‐blockers have been recommended for rate control by the International Society of Heart and Lung transplantation (ISHLT) . Previous data revealed that β‐blockers should be used with caution in cardiac transplant recipients due to their negative effect on ventricular performance, as well as on exercise tolerance and on cardiovascular response to exercise …”