What is hypertensive cardiomyopathy?

Hypertensive Cardiomyopathy: Definition and Clinical Features

Hypertensive cardiomyopathy is a cardiac condition characterized by left ventricular hypertrophy (LVH) resulting from chronic uncontrolled hypertension, which can progress from a compensated state to heart failure with preserved ejection fraction and potentially to dilated cardiomyopathy with systolic dysfunction in end-stage disease. 1

Pathophysiology and Development

• Hypertensive cardiomyopathy develops as an adaptive response to chronic pressure overload, initially manifesting as concentric LVH with normal or preserved ejection fraction 2
• The condition is characterized by myocardial fibrosis (both reactive and replacement), abnormal pressure-volume relationships in the left ventricle, and increased left ventricular filling pressures 2
• Microvascular changes occur, including decreased intramyocardial capillary density, coronary arteriolar thickening, and decreased coronary blood flow reserve 2
• Biomarkers such as NT-proBNP, BNP, or troponin are typically elevated 2

Clinical Features and Progression

• Hypertensive cardiomyopathy typically follows a progression from compensated hypertrophy to heart failure 2
• The condition initially presents with concentric LVH, normal ejection fraction, and normal or decreased end-diastolic volume 2
• As the disease progresses, there is often an increase in left ventricular end-diastolic and end-systolic volumes with decreased ejection fraction, signaling an ominous transition 2
• Increased left ventricular chamber stiffness and impaired active relaxation can lead to heart failure with preserved ejection fraction (HFpEF) 1
• In advanced stages, the condition may progress to dilated cardiomyopathy with systolic dysfunction 1

Diagnostic Considerations

• Most patients with hypertensive LVH have maximal interventricular septal thickness <15mm, which helps distinguish them from patients with hypertrophic cardiomyopathy 1
• Regression of LVH with tight blood pressure control over 6-12 months supports a hypertensive etiology 1
• Echocardiography typically shows concentric LVH, which may be associated with mild systolic dysfunction and diastolic dysfunction 3
• Cardiovascular magnetic resonance feature tracking strain analysis can help differentiate between hypertensive heart disease and hypertrophic cardiomyopathy 4

Differentiation from Hypertrophic Cardiomyopathy

• Hypertensive cardiomyopathy must be distinguished from genetic hypertrophic cardiomyopathy (HCM) caused by sarcomere protein mutations 2
• In older patients with LVH and systemic hypertension, definitive diagnosis can be challenging, particularly when LV wall thickness is less than 20 mm and systolic anterior motion (SAM) is absent 2
• Marked LVH disproportionate to the level of blood pressure elevation, unusual patterns of LVH unique to HCM, or obstruction to LV outflow at rest represents presumptive evidence for HCM rather than hypertensive cardiomyopathy 2
• Global longitudinal strain (GLS) assessment by cardiac MRI can help differentiate between hypertensive heart disease and HCM 4

Management Approach

• Aggressive blood pressure control targeting BP <130/80 mmHg is the cornerstone of management 1
• ACE inhibitors or ARBs are recommended as first-line therapy to reduce remodeling and improve outcomes 1
• Beta-blockers are essential components of therapy, targeting a resting heart rate between 50-60 beats per minute 1
• Thiazide or thiazide-type diuretics are recommended as first-choice agents for BP control and prevention of heart failure progression 1
• Aldosterone antagonists should be considered in patients with heart failure symptoms 1
• Medications to avoid include non-dihydropyridine calcium channel blockers, clonidine, moxonidine, and alpha-blockers due to potential worsening of heart failure symptoms or increased mortality 1

Prognosis and Reversibility

• With appropriate antihypertensive therapy, even severe LVH can be reversible 3
• Studies have shown significant reduction in left ventricular mass index, improvement in systolic function, and improvement in diastolic dysfunction after only 6 months of combination antihypertensive therapy 3
• Early and aggressive intervention is critical to prevent progression to irreversible heart failure 1

Common Pitfalls and Caveats

• Hypertensive cardiomyopathy may coexist with other cardiac conditions such as coronary artery disease, requiring management of each condition on its own merit 2
• ACE inhibitors should be avoided in patients with concurrent hypertrophic cardiomyopathy who have resting or provocable LV outflow tract obstruction 2
• Failure to exclude coronary artery disease in patients with angina pectoris is a common pitfall 2
• Distinguishing between hypertensive cardiomyopathy and hypertrophic cardiomyopathy with hypertension can be challenging, especially in elderly patients 5