What is the best approach to manage left ventricular hypertrophy?

Management of Left Ventricular Hypertrophy

The best approach to manage left ventricular hypertrophy (LVH) depends on its underlying etiology, with treatment focusing on controlling the primary cause while implementing targeted therapies to reduce LV mass and improve outcomes related to morbidity and mortality. 1, 2

Etiology-Based Management Approach

Hypertension-Induced LVH

• ARBs, particularly losartan, are preferred first-line agents for LVH regression due to superior efficacy in reducing left ventricular mass and myocardial fibrosis compared to beta-blockers 2
• ACE inhibitors are equally effective alternatives when ARBs aren't tolerated 2
• Calcium channel antagonists, particularly non-dihydropyridines like verapamil and diltiazem, have demonstrated significant efficacy in LVH regression 2
• Aldosterone antagonists (eplerenone) have shown efficacy equal to ACE inhibitors in reducing LVH 2
• Blood pressure control should remain the primary goal of therapy, as adequate BP reduction is essential for LVH regression 2

Hypertrophic Cardiomyopathy (HCM) with LVOTO

• Non-vasodilating β-blockers titrated to maximum tolerated dose are first-line therapy for symptomatic patients with LVOTO 1
• If β-blockers alone are ineffective, disopyramide may be added (usually 400-600 mg/day), which can abolish basal LV outflow pressure gradients and improve exercise tolerance 1
• Verapamil (starting at 40 mg three times daily to maximum 480 mg daily) can be used when β-blockers are contraindicated or ineffective 1
• Diltiazem (starting at 60 mg three times daily to maximum 360 mg daily) should be considered in patients intolerant to β-blockers and verapamil 1
• Avoid arterial and venous dilators, including nitrates and phosphodiesterase inhibitors, in patients with resting or provocable LVOTO 1
• Digoxin is not recommended in patients with LVOTO due to its positive inotropic effects 1

Non-Obstructive HCM

• Focus on management of arrhythmias, reduction of LV filling pressures, and treatment of angina 1
• For patients with progressive LV systolic or diastolic dysfunction refractory to medical therapy, cardiac transplantation may be considered 1

General Management Principles

Assessment and Monitoring

• Echocardiography is more sensitive than electrocardiography in detecting LVH and should be used for diagnosis and monitoring 1
• Proper evaluation includes measurements of interventricular septum, LV posterior wall thickness, end-diastolic diameter, and calculation of LV mass 1
• For HCM patients with symptoms, assess for LVOTO with 2D and Doppler echocardiography during Valsalva maneuver in sitting, semi-supine, and standing positions 1
• Exercise stress echocardiography is recommended in symptomatic patients if bedside maneuvers fail to induce LVOTO ≥50 mm Hg 1

Diastolic Dysfunction Management

• Diastolic dysfunction is common in LVH and contributes to decreased exercise capacity and adverse prognosis 1
• With impaired ventricular relaxation, patients have greater dependency on atrial systole for ventricular filling, leading to poor tolerance of atrial fibrillation 1
• Prompt restoration of sinus rhythm or appropriate rate control should be considered in patients with new-onset or poorly controlled atrial fibrillation 1

Lifestyle Modifications

• All patients with LVOTO should avoid dehydration and excess alcohol consumption 1
• Weight loss should be encouraged in overweight/obese patients 1
• Intensive modification of cardiometabolic risk factors (obesity, hypertension, diabetes, obstructive sleep apnea) is important as these are highly prevalent in HCM patients and associated with poorer prognosis 1

Clinical Benefits of LVH Regression

• Treatment-induced reduction in left ventricular mass is significantly and independently associated with reduction in major cardiovascular events, stroke, and cardiovascular and all-cause mortality 2
• LVH regression typically achieves maximum effect after 2-3 years of consistent treatment 2

Common Pitfalls and Caveats

• Nifedipine and other dihydropyridine calcium antagonists are not recommended for treatment of LVOTO 1
• Low-dose loop or thiazide diuretics may be used cautiously to improve dyspnea associated with LVOTO, but it's important to avoid hypovolaemia 1
• Using dobutamine to identify latent LVOTO is not advised due to lack of specificity 1
• Disopyramide should be avoided in patients with glaucoma, in men with prostatism, and in patients taking other drugs that prolong the QT interval 1
• The QTc interval should be monitored during disopyramide dose up-titration and the dose reduced if it exceeds 480 ms 1