Contemporary family screening in hypertrophic cardiomyopathy: the role of cardiovascular magnetic resonance . (7th June 2022)

• Record Type: Journal Article
• Authors: Huurman, Roy; van der Velde, Nikki; Schinkel, Arend F L; Hassing, H Carlijne; Budde, Ricardo P J; van Slegtenhorst, Marjon A; Verhagen, Judith M A; Hirsch, Alexander; Michels, Michelle
• Is Part Of: European heart journal. Volume 23:Number 9(2022)
• Page Start: 1144
• Page End: 1154
• Publication Date: 2022-06-07
• Subjects: hypertrophic cardiomyopathy -- echocardiography -- cardiovascular magnetic resonance -- genetics -- screening; Cardiovascular system -- Imaging -- Periodicals; Heart -- Imaging -- Periodicals; 616.10754
• DOI: 10.1093/ehjci/jeac099
• Languages: English
• ISSNs: 2047-2404

Abstract

Abstract: Aims: Genetic testing in relatives of hypertrophic cardiomyopathy (HCM) patients leads to early identification of pathogenic DNA variant carriers (G+), before the onset of left ventricular hypertrophy. Routine phenotyping consists of electrocardiography (ECG) and transthoracic echocardiography (TTE). Cardiovascular magnetic resonance (CMR) has become valuable in the work-up of HCM. In this study, we investigated the value of CMR in phenotyping of G+ family members. Methods and results: This study included 91 G+ subjects who underwent ECG, TTE and CMR, with a maximal wall thickness (MWT) <15 mm on TTE. The relative performance of TTE and CMR regarding wall thickness measurements and HCM diagnoses was assessed. HCM was defined as MWT of ≥13 mm. Logistic regression was performed to assess whether ECG and TTE parameters can predict CMR results. Most subjects (75%) had an MWT <13 mm on TTE, of which 23 (34%) were diagnosed with HCM based on CMR. MWT differences (range 1–10 mm) were often caused by an anterobasal hook-shaped thickening of the myocardium not visible on TTE. Two of 23 (9%) subjects with HCM on TTE were reclassified as no HCM on CMR. Normal ECG and TTE results almost excluded reclassifications by CMR. The prevalence of other HCM-related abnormalities on CMR was low. Conclusion: CMR reclassified 27% of subjects. Subjects with normal ECG/TTE results were reclassified in a low number of cases, justifying screening with ECG and TTE in G+ relatives. In subjects with abnormal ECGs and/or poor TTE image quality, CMR is indicated. Graphical Abstract: Graphical Abstract Overview of current study as a structured abstract in top left, demonstrating the use of cardiac magnetic resonance imaging (CMR) on top of electrocardiography (ECG) and transthoracic echocardiography (TTE) in subjects evaluated for hypertrophic cardiomyopathy (HCM) through family screening. Presence or absence of HCM as judged by TTE and CMR imaging is cross-tabulated (1). More than a quarter of subjects are reclassified when using CMR, as shown by the red boxes. Reclassifications mostly occurred in subjects without HCM on TTE (23/68, 34%), and only rarely in those with HCM on TTE (2/23, 9%). In 10 subjects reclassified as HCM on CMR, a prominent anterobasal hook was found on CMR, a structure not visible on TTE (2, arrows). Results from ECG and TTE can be used to predict diagnoses on HCM (3), as subjects with normal ECG/TTE results (defined as the absence of left ventricular hypertrophy on ECG or TTE, and the lack of left ventricular outflow tract obstruction on TTE), were reclassified in only a small number of cases. These findings highlight the potential role of CMR in family screening for HCM, and show how ECG and TTE can be used to assess whether or not it is useful to perform CMR studies in this subject group. G+ = genotype positive.