Cardiac Morpho-Functional Changes, Inflammation and Fibrosis in Systemic Sclerosis-A Pilot Study of a Tertiary Center Cohort

Abstract

Background: Cardiac involvement (CI) in systemic sclerosis (SSc) is frequently subclinical and it can be identified in up to 80% of autopsied hearts. If present, symptoms are related to adverse prognosis, and CI represents one of the predominant causes of SSc-related mortality. Methods: A total of 20 patients with a diagnosis of SSc were included and followed up, and 37 volunteers were included and subsequently scanned on a 1.5T MR system. Results: Overall, thirteen (65%) patients had one or more abnormal cardiac findings in CMR (defined as CI[+]), of which in seven (35%), baseline ECGs and standard echocardiograms were normal or unspecific. Compared to healthy volunteers, SSc patients had a lower LVEF% (56.6% vs. 61.6%; p = 0.0131), longer T1 (1028.3 ms vs. 993.1 ms; p = 0.0049) and T2 relaxation times (48.24 ms vs. 43 ms p = 0.0011), and higher extracellular volume (ECV, 27.9% vs. 26.0%; p = 0.0112). However, no difference in CMR-derived, feature-tracking GLS values between patients and healthy controls was found (-15.5[2,8] vs. -16.3[1,1], respectively, p = 0.11). Over 3.4 (1.9-5.5) years, three patients (15%) died, and two others (10%) sustained major cardiac complications. Conclusions: Cardiac magnetic resonance with modern quantitative techniques reveals subtle morpho-functional alterations and thus allows for early diagnosis of myocardial involvement in systemic sclerosis. Our findings emphasize the need for extended diagnostic workup in these patients and demonstrate the ability of cardiac MR to select patients requiring closer follow-up and/or treatment decisions.

Keywords: cardiac magnetic resonance; heart involvement; systemic sclerosis.

Figure 1

(A–C) Sixty-six-year-old woman with a recent (6 months prior) DSSc diagnosis, normal transthoracic echocardiography, borderline LV size, and normal function on CMR (LVEDVI of 99 mL/m² [ref. range 61–95 mL/m²] and LVEF of 65%, GLS of −17.4% (within the reference range)), normal standard ECG and paroxysmal second degree AV block. (A) T2-weighted images (T2STIR) showed high signal within the basal segments of the inferior and inferoseptal wall (ratio of myocardial to skeletal muscle signal >2), matched by locally increased T2 relaxation time of 55 ms in the inferior wall. The institutional reference range for T2 time was 39–49 ms ((B), arrow). Images (A,B) are consistent with localized myocardial edema. In (C), locally increased native T1 relaxation time (1081 ms) can be noted (the institutional reference range 953–1035 ms), corresponding both to edema and to subtle areas of disperse subendocardial late gadolinium enhancement in the inferior wall. (D–F) Patterns of inflammatory injury in SSc patients, late gadolinium enhancement images. (D) Fourty-one year-old female patient with DSSc, with generalized subendocardial late gadolinium enhancement (arrows), suggestive of the presence of a degree of irreversible injury in the subendocardium. (E) Fifty-nine-year-old male SSc patient with overt heart involvement, elevated BNP, enlarged ventricles and reduced LVEF of 41%. Nonischemic intramyocardial late gadolinium enhancement in the basal inferior wall in the short axis. (F) Sixty-five-year-old female patient 2 yrs from DSSc diagnosis, with normal echocardiography, and normal ECG; subtle dispersed generalized late gadolinium enhancement can be noted (arrowheads). (Siemens Aera 1.5T, Erlangen, Germany). AV—atrio-ventricular, BNP—brain natriuretic peptide, CMR—cardiac magnetic resonance, GLS—global longitudinal strain, LVEDVI—left ventricular end-diastolic volume index, LVEF—left ventricular ejection fraction, T2STIR—T2-weighted short-tau inversion recovery sequence.