Chapter 10 Cardiac Disease Populations (2022)

Cardiac Disease Overview

Introduction

Cardiac disease encompasses a variety of conditions that affect the heart and blood vessels, necessitating interventions such as cardiopulmonary rehabilitation (CR) and secondary prevention programs. This document outlines essential considerations regarding various populations affected by cardiac disease, treatment options, and post-surgical care.

Purpose and Scope

The primary purpose of this chapter is to provide insights into different cardiovascular disease (CVD) populations commonly referred for rehabilitation, including:

• Patients with a history of myocardial infarction (MI), revascularization, and stable angina.

• Individuals undergoing heart valve replacement or repair surgeries.

• Patients with dysrhythmias, those with pacemakers or implantable cardioverter-defibrillators (ICDs), as well as those with heart failure or left ventricular assist devices (LVADs).

• Individuals who have undergone cardiac transplantation and patients with peripheral arterial disease (PAD).

Revascularization and Valve Surgery

Surgical Techniques

Several revascularization procedures are critical in managing coronary artery disease (CAD) caused by atherosclerosis:

• Coronary Artery Bypass Grafting (CABG) and Minimally Invasive Direct Coronary Artery Bypass (MID-CAB)

• Percutaneous Coronary Intervention (PCI) The annual statistics provided by the American Heart Association (AHA) reveal a growing number of these procedures, with 397,000 CABGs and 954,000 PCIs performed each year in the U.S.

Patient Demographics

It is noteworthy that males represent approximately 70% of these procedures, highlighting a significant gender disparity in the prevalence of cardiac interventions.

Special Considerations for Patients Following Interventions

Coronary Artery Bypass Grafting (CABG)

• Evaluating the revascularization results, addressing any graft occlusion, and emphasizing exercise precautions for upper extremities are crucial.

• Patients may minimize the seriousness of coronary heart disease (CHD), viewing surgery as a "cure" instead of a component of ongoing management. Comprehensive services for secondary prevention are vital for these patients.

Percutaneous Coronary Intervention (PCI)

• Similar to CABG, patients must be monitored for restenosis or thrombosis at PCI sites and be made aware of the ongoing nature of their disease progress.

Valvular Heart Disease (VHD)

• Patients require anticoagulation therapy and must take precautions regarding exercise to prevent bleeding and injuries.

• Exercise regimens should avoid resistance-type exercises with severe aortic stenosis or insufficiency due to increased stress on the heart.

Dysrhythmias in Cardiac Rehabilitation

Types of Cardiac Dysrhythmias

1. Generally Benign Dysrhythmias:

   • Premature Atrial Complexes (PACs), Premature Ventricular Complexes (PVCs), and controlled Atrial Fibrillation (A-fib).

   • Mild bradycardia and first-degree AV block.

2. Potentially Malignant Dysrhythmias:

   • Rapid Atrial Fibrillation, symptomatic bradycardia, ventricular tachycardia, and ventricular fibrillation can be life-threatening and require monitoring.

Symptoms of Dysrhythmias

• Stable Symptoms: Palpitations, dizziness, shortness of breath, and chest pain are common but should be monitored closely.

• Unstable Symptoms: More severe symptoms such as hypotension and near-syncope indicate a critical need for medical evaluation.

Pacemakers and IC Devices

Pacemaker Functionality

Advancements in cardiac pacemaker technologies have allowed for effective physiological responses during exercise:

• Atrioventricular pacing ensures proper timing of heart contractions, enhancing exercise capacity.

• Rate-responsive pacemakers adapt pacing rates based on activity levels to optimize cardiac output.

Considerations for Patients with ICDs

• Exercise training is generally safe for ICD patients post-6 months of intervention.

• It is important to manage exercise intensity below the detected ventricular tachycardia or fibrillation heart rates to minimize risks.

Heart Failure and Left Ventricular Assist Devices (LVADs)

Epidemiology and Impact

Heart failure (HF) affects over 5.7 million Americans annually, with significant hospitalization rates and mortality:

• Approximately 670,000 new cases arise yearly.

• About 50% of HF patients may die within five years of diagnosis, accumulating substantial healthcare costs.

Clinical Manifestations

Symptoms include:

• Dyspnea, fatigue, and tachypnea.

• Peripheral edema and weight gain may indicate worsening heart function.

LVAD Function in Heart Failure Patients

The LVAD helps alleviate symptoms by assisting cardiac output, but patients may experience challenges such as diastolic dysfunction and impaired vascular responses.

Cardiac Transplantation

Overview of Process

Cardiac transplantation is a complex procedure with a wide spectrum of comorbidities post-transplant, necessitating ongoing care:

• Approximately 3,000 heart transplant surgeries are conducted each year globally.

• Long-term immunosuppression is crucial to prevent rejection while also managing potential adverse effects like hypertension and diabetes.

Physiological Responses

Transplanted hearts face unique physiological challenges that can affect exercise tolerance and recovery, including abnormal heart rate responses and potential peripheral vascular insufficiency.

Peripheral Artery Disease (PAD)

Characteristics and Symptoms

PAD results from systemic atherosclerosis, leading to significant walking-induced pain:

• Patients may experience claudication, indicative of arterial blockages.

• Critical limb ischemia presents as severe burning pain that can threaten limb viability and warrants immediate referral.