Commentary: Pulmonary hypertension and survival in hypertrophic cardiomyopathy: A predictor or a surrogate?

Central MessagePulmonary hypertension is present in almost half of the patients with hypertrophic cardiomyopathy and is associated with worse survival.See Article page XXX. Management of hypertrophic cardiomyopathy (HCM) has evolved over the last several decades, aided by refinements in risk-stratification tools that tailor treatment strategies. The innovations in surgical techniques provide durable benefit, and improvements in medical therapies help to minimize overall morbidity.1Berger S. Sjaastad I. Stokke M.K. Right ventricular involvement in hypertrophic cardiomyopathy: evidence and implications from current literature.Scand Cardiovasc J. 2021; 55: 195-204https://doi.org/10.1080/14017431.2021.1901979Crossref PubMed Scopus (3) Google Scholar In appropriately selected patients, surgical (septal) myectomy has become an effective, low-risk operation with anatomical (based on hemodynamic parameters) and clinical benefits (based on patient symptoms). Nonetheless, several key questions still remain unanswered, including the optimal timing of surgery for severe symptoms despite optimal medical therapy (Class I guidelines), or those with severe pulmonary hypertension (PH), left atrial dilatation with associated risk of atrial fibrillation, severe mitral regurgitation, or severe heart failure (Class IIb guidelines).2Maron B. Desai M. Nishimura R. Spirito P. Rakowski H. Towbin J.A. et al.Management of hypertrophic cardiomyopathy.J Am Coll Cardiol. 2022; 79: 390-414Crossref PubMed Scopus (27) Google Scholar,3Ommen S.R. Mital S. Burke M.A. Day S.M. Deswal A. Elliott P. et al.2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: a report of the American College of Cardiology/American Heart Association Joint Committee on clinical practice guidelines.J Thorac Cardiovasc Surg. 2021; 162: e23-e106Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar We read with great interest the paper by Ahmed and colleagues,4Ahmed E.A. Schaff H.V. Al-Lami H.S. Lahr B.D. Dearani J.A. Nishimura R.A. et al.Prevalence and influence of pulmonary hypertension in patients with obstructive hypertrophic cardiomyopathy undergoing septal myectomy.J Cardiovasc Thorac Surg. September 7, 2022; ([Epub ahead of print])Abstract Full Text Full Text PDF Scopus (2) Google Scholar which attempts to answer the aforementioned question and raise awareness of the prognostic value of preoperative PH in the context of optimal timing of intervention and long-term survival. To their credit, the authors used their extensive 30-year surgical experience with HCM to determine the prevalence and impact of PH in patients undergoing surgical myectomy. They found that PH was present in almost half of the patients, and those with at least mild PH had worse survival compared with those without PH. The correlation between PH and mortality seems valid, and despite the underlying patient-selection biases (in terms of those who undergo surgery), these findings provide some food for thought: First, PH appears to be a predictor of worse survival, and second, surgical myectomy may potentially provide greater benefit to patients if offered earlier in their clinical course rather than waiting until the progression of symptoms as highlighted in the guidelines. This aggressive approach may halt the irreversible pulmonary endothelial remodeling that may be associated with long-term right ventricular dysfunction and worse survival.5Covella M. Rowin E.J. Hill N.S. Preston I.R. Milan A. Opotowsky A.R. et al.Mechanism of progressive heart failure and significance of pulmonary hypertension in obstructive hypertrophic cardiomyopathy.Circ Heart Fail. 2017; 10: e003689Crossref PubMed Scopus (33) Google Scholar Given the high incidence of myocardial fibrosis and sudden cardiac death in this patient cohort,5Covella M. Rowin E.J. Hill N.S. Preston I.R. Milan A. Opotowsky A.R. et al.Mechanism of progressive heart failure and significance of pulmonary hypertension in obstructive hypertrophic cardiomyopathy.Circ Heart Fail. 2017; 10: e003689Crossref PubMed Scopus (33) Google Scholar it remains paramount that clinicians perform systematic, thorough, and nuanced investigations to provide optimal treatment in the current era of precision medicine. While PH appears to be an important additional variable to assist with patient selection, it remains to be determined whether PH is a consequence of HCM or a surrogate for worsening cardiac dysfunction. This study doesn't delineate between the two but perhaps using either a contrast-enhanced cardiovascular magnetic resonance imaging with late gadolinium enhancement or myocardial biopsy may have provided further guidance in determining ideal candidates and timing for surgical myectomy6Chan R.H. Maron B.J. Olivotto I. Pencina M.J. Assenza G.E. Haas T. et al.Prognostic value of quantitative contrast-enhanced cardiovascular magnetic resonance for the evaluation of sudden death risk in patients with hypertrophic cardiomyopathy.Circulation. 2014; 130: 484-495Crossref PubMed Scopus (586) Google Scholar in the absence of large-scale data or randomized clinical trials. Prevalence and influence of pulmonary hypertension in patients with obstructive hypertrophic cardiomyopathy undergoing septal myectomyThe Journal of Thoracic and Cardiovascular SurgeryPreviewPulmonary hypertension (PH) is an independent predictor of all-cause mortality among patients with obstructive and nonobstructive hypertrophic cardiomyopathy (HCM). However, there is little information on the influence of coexisting PH on long-term survival following septal myectomy. This study investigates the prevalence of PH among patients with obstructive HCM undergoing septal myectomy and analyzes patient survival and the course of PH after operation. Full-Text PDF