Ventricular pacing improves exercise tolerance in patients with chronic heart block

Area of Science:

• Cardiology
• Biomedical Engineering

Background:

• Heart block can cause debilitating breathlessness.
• Patients with heart block often experience reduced exercise capacity.

Purpose of the Study:

• To evaluate the impact of transvenous, ventricular, demand pacing on exercise capacity in heart block patients.
• To assess the symptomatic benefit and objective improvement in exercise capacity following pacing.

Main Methods:

• A six-minute walking test was used to assess exercise capacity.
• 18 heart block patients (study group) were evaluated before and after pacemaker implantation.
• 8 patients with existing pacemakers (control group) underwent generator replacement for comparison.

Main Results:

• Exercise capacity significantly increased within 48 hours of ventricular pacing in the study group.
• Improvements in exercise capacity were maintained for up to 30 months.
• No significant change in exercise capacity was observed in the control group after generator replacement.

Conclusions:

• Transvenous, ventricular, demand pacing provides significant symptomatic and objective benefits for heart block patients with breathlessness.
• The six-minute walking test is a reliable tool for assessing pacing-induced improvements in exercise capacity.
• Ventricular pacing is an effective treatment for improving quality of life in selected heart block patients.