Evolución clínica y reversibilidad de la disfunción sistólica en pacientes con miocardiopatía dilatada hipertensiva e insuficiencia cardíaca crónica

Concept of myocardial fatigue in reversible severe left ventricular systolic dysfunction from afterload mismatch: a case series

Background 

There is already extensive literature on the natural history of hypertensive heart disease (HHD) and aortic stenosis (AS). Once these patients develop severe left ventricular systolic dysfunction (LVSD) despite guideline-directed therapy for heart failure (HF), it is often thought to be end-stage from irreversible adverse remodelling. Our case series challenges this traditional paradigm. A more holistic model that factors in the interactions between the ventricle and vasculature is required. Based on a novel hypothetical concept of myocardial fatigue, we propose that occasionally LVSD is not an inherent myocardial or valvular disease but a consequence of an arterial afterload mismatch. By addressing this, the ventricle may recover and contract efficiently in unison with the arterial system.

Case summary 

We present two cases of severe LVSD in a young lady with long-standing essential hypertension and a gentleman with stable severe AS. Both patients were already established on HF medications. After optimizing their blood pressure control, repeat echocardiography revealed normalization of left ventricular ejection fraction within 3 months, along with a demonstrable improvement in ventricular-arterial coupling and for AS, a reduction in valvular-arterial impedance.

Discussion 

Just as Frank-Starling's law was discovered by initially drawing analogies to skeletal muscle behaviour, it is biologically plausible that cardiac fatigue can occur in the setting of afterload mismatch. The chance of recovery rests upon early recognition before it transitions to irreversible myocardial damage. Only by testing new emerging theories of HF can we galvanize original research and find new avenues to understanding this complex syndrome.

Hypertensive heart disease: Benefit of carvedilol in hemodynamic, left ventricular remodeling, and survival

Objectives

The aim of this study was to determine if carvedilol improved structural and functional changes in the left ventricle and reduced mortality in patients with hypertensive heart disease.

Methods

Blood pressure, heart rate, echocardiographic parameters, and laboratory variables, were assessed pre and post treatment with carvedilol in 98 eligible patients.

Results

Carvedilol at a median dose of 50 mg/day during the treatment period in hypertensive heart disease lowered blood pressure 10/10 mmHg, heart rate 10 beats/min, improved left ventricular ejection fraction from baseline to follow-up (median: 6 years) (36%-47%)) and reduced left ventricular end-diastolic and end-systolic dimensions (62 vs 56 mm; 53 vs 42 mm, respectively, all p-values <0.01). Left ventricular ejection fraction increased in 69% of patients. Patients who did not have improved left ventricular ejection fraction had nearly six-fold higher mortality than those that improved (relative risk; 5.7, 95% confidence interval: 1.3-25, p = 0.022).

Conclusion

Carvedilol reduced cardiac dimensions and improved left ventricular ejection fraction and cardiac remodeling in patients with hypertensive heart disease. These treatment-related changes had a favorable effect on survival.