Cardiac function and mechanics in systemic sclerosis: a systematic review and meta-analysis

The study aimed to evaluate differences in conventional, tissue Doppler imaging (TDI) and speckle-tracking echocardiographic (STE) parameters of all cardiac chambers between SSc patients and healthy controls.

A study search strategy based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed. MEDLINE, Scopus and Web of Science were searched using the following keywords: "speckle tracking", "global strain", "longitudinal strain", "circumferential strain", "radial strain", "atrial strain", "right ventricular strain", or "left ventricular strain" and "systemic sclerosis". Primary pooled analyses were performed on each cardiac parameter independently to determine the weighted mean difference (WMD) between SSc and controls. Further independent subgroup analyses were performed to compare symptomatic vs asymptomatic SSc and diffuse vs limited SSc.

The systematic review and meta-analysis included 41 case-control eligible reports studies with a pooled sample size of 2497 SSc cases and 1439 controls. Significant weighted mean differences (WMD) between SSc patients and healthy controls were identified in septal S' wave (WMD 0.343 cm/s, CI [- 0.540-0.145], I²: 36%, p = 0.001), lateral S' wave (WMD 0.795 cm/s, CI [- 1.394-0.197], I²: 0%, p = 0.009), tricuspid S' wave (WMD 1.137 cm/s, CI [- 1.784-0.489], I²: 84%, p = 0.001), septal e' wave (WMD 1.398 cm/s, CI [- 2.272-0.523], I²: 82%, p = 0.002) and lateral e' wave (WMD 3.545 cm/s, CI [- 4.990-2.100], I²: 71%, p < 0.001) velocities. STE parameters were attenuated in patients with SSc, with impairment of left ventricular global longitudinal (WMD 2.765%, CI [- 3.482-2.049], I²: 91%, p < 0.001), circumferential (WMD 3.145%, CI [- 4.181-2.109], I²: 79%, p < 0.001), and radial (WMD 4.044%, CI [- 6.199-1.889], I²: 0%, p < 0.001) strain, right ventricular free wall (WMD 4.492%, CI [- 6.048-2.937], I²: 76%, p < 0.001) and right ventricular global longitudinal strain (WMD 2.843%, CI [- 3.290-2.396], I²: 32%, p < 0.001), as well as left (WMD - 8.317%, CI [- 11.873-4.761], I²: 82%, p < 0.001) and right (WMD 7.346%, CI [- 10.536-4.156], I²: 26%, p < 0.001) atrial reservoir strain.

SSc is associated with significantly impaired cardiac function and mechanics compared to healthy individuals, even in the absence of symptoms or pulmonary hypertension.