Left Ventricular Myocardial Remodeling and Prognostic Marker Derived from Postmyectomy Cardiac MRI Feature Tracking in Hypertrophic Obstructive Cardiomyopathy.

Purpose: To investigate myocardial remodeling using cardiac MRI (CMR) feature tracking (FT) and to explore the relationship between CMR parameters with outcomes in hypertrophic obstructive cardiomyopathy (HOCM) after myectomy. Materials and
Methods: In this single-center retrospective study, patients with HOCM undergoing myectomy between 2011 and 2019 were included. Pre- and postmyectomy global and regional strains were compared. Healthy participants were included for comparison. Composite events were recorded at follow-up performed after a minimum of 12 months. The paired-samples t test was utilized to compare pre- and postmyectomy variables.
Results: A total of 73 patients (44 years ± 14 [SD]; 45 men) were evaluated. Compared with preoperative parameters, global circumferential strain (CS) (-17.6% ± 4.4 vs -16.7% ± 3.9, P = .02) was impaired, but global longitudinal strain (LS) was improved (-9.3% ± 2.8 vs -10.8% ± 3.3, P < .001). Septal CS (-14.2% ± 4.0 vs -11.0% ± 4.4, P < .001) and septal radial strain (RS) (16.4% ± 10.6 vs 13.7% ± 9.5, P = .007) worsened, while septal LS (-8.1% ± 3.5 vs -10.2% ± 3.4, P < .001), lateral RS (40.1% ± 16.6 vs 54.4% ± 22.6, P < .001), lateral CS (-20.2% ± 4.1 vs -23.1% ± 4.8, P < .001), and lateral LS (-5.6% ± 5.6 vs -8.4% ± 5.2, P = .001) were improved. Sixteen of 73 patients (22%) experienced composite events after median follow-up of 39.1 months. Postoperative global CS provided the highest discrimination for composite event occurrence (area under the receiver operating characteristic curve, 0.73; 95% CI: 0.61, 0.83) with a cutoff of -16.7%. Patients with postoperative global CS greater than -16.7% had reduced event-free survival compared with those with postoperative global CS less than or equal to -16.7% (log-rank P = .002).
Conclusion: CMR-FT analysis demonstrated longitudinal and lateral restorations, but impaired global CS, after myectomy in patients with HOCM; furthermore, increased global CS was associated with poorer outcomes.Keywords: MR Imaging, Cardiac, Outcomes Analysis, Comparative Studies, Surgery© RSNA, 2022 Supplemental material is available for this article. 2022 by the Radiological Society of North America, Inc.