Systolic blood pressure ≤110 mm Hg is associated with severe coronary microvascular ischemia and higher risk for ventricular arrhythmias in hypertrophic cardiomyopathy

Dai-Yin Lu; Hulya Yalcin; Fatih Yalcin; Sanjay Sivalokanathan; Gabriela V Greenland; Ioannis Ventoulis; Styliani Vakrou; Miguel Hernandez Pampaloni; Stefan L Zimmerman; Ines Valenta; Thomas H Schindler; Theodore P Abraham; M Roselle Abraham

doi:10.1016/j.hroo.2023.07.009

Systolic blood pressure ≤110 mm Hg is associated with severe coronary microvascular ischemia and higher risk for ventricular arrhythmias in hypertrophic cardiomyopathy

Heart Rhythm O2. 2023 Aug 4;4(9):538-548. doi: 10.1016/j.hroo.2023.07.009. eCollection 2023 Sep.

Authors

Dai-Yin Lu^{1

2

3}, Hulya Yalcin^{1

3}, Fatih Yalcin^{1

3}, Sanjay Sivalokanathan^{1

3}, Gabriela V Greenland^{1

3}, Ioannis Ventoulis^{1

4}, Styliani Vakrou¹, Miguel Hernandez Pampaloni⁵, Stefan L Zimmerman⁶, Ines Valenta⁶, Thomas H Schindler⁶, Theodore P Abraham^{1

3}, M Roselle Abraham^{1

3}

Affiliations

¹ Hypertrophic Cardiomyopathy Center of Excellence, Johns Hopkins University, Baltimore, Maryland.
² Institute of Public Health, National Yang Ming Chiao Tung University, Taipei, Taiwan.
³ Division of Cardiology, University of California San Francisco, San Francisco, California.
⁴ Department of Occupational Therapy, University of Western Macedonia, Ptolemaida, Greece.
⁵ Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California.
⁶ Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland.

Abstract

Background: Coronary microvascular dysfunction (CMD) and hypertension (HTN) occur frequently in hypertrophic cardiomyopathy (HCM), but whether blood pressure (BP) influences CMD and outcomes is unknown.

Objective: The purpose of this study was to test the hypothesis that HTN is associated with worse CMD and outcomes.

Methods: This retrospective study included 690 HCM patients. All patients underwent cardiac magnetic resonance imaging, echocardiography, and rhythm monitoring; 127 patients also underwent rest/vasodilator stress ¹³NH₃ positron emission tomography myocardial perfusion imaging. Patients were divided into 3 groups based on their rest systolic blood pressure (SBP) (group 1 ≤110 mm Hg; group 2 111-140; group 3 >140 mm Hg) and were followed for development of ventricular tachycardia (VT)/ventricular fibrillation (VF), heart failure (HF), death, and composite outcome.

Results: Group 1 patients had the lowest age and left ventricular (LV) mass but the highest prevalence of nonobstructive hemodynamics and restrictive diastolic filling. LV scar was similar in the 3 groups. Group 1 had the lowest rest and stress myocardial blood flow (MBF) and highest SDS (summed difference score). Rest SBP was positively correlated with stress MBF and negatively correlated with SDS. Group 1 had the highest incidence of VT/VF, whereas the incidences of HF, death, and composite outcome were similar among the 3 groups. In multivariate analysis, rest SBP ≤110 mm Hg was independently associated with VT/VF (hazard ratio 2.6; 95% confidence interval 1.0-6.7; P = .04).

Conclusion: SBP ≤110 mm Hg is associated with greater severity of CMD and coronary microvascular ischemia and higher incidence of ventricular arrhythmias in HCM.

Keywords: Hypertrophic cardiomyopathy; Myocardial blood flow; Rest systolic blood pressure; Summed difference score; Ventricular fibrillation; Ventricular tachycardia.