Background: The development of postprocedural systemic inflammatory response syndrome (SIRS) is a common clinical finding after cardiovascular interventions. Analysis of the incidence of SIRS and its impact on mortality in patients undergoing transcatheter edge-to-edge mitral valve repair (MV-TEER) for moderate or severe mitral regurgitation (MR) do not exist so far. Therefore, we investigated the incidence and prognosis of SIRS in an all comers cohort of patients undergoing MV-TEER.

Methods: 373 patients with moderate or severe MR undergoing MV-TEER between January 2013 and December 2020 were included. SIRS definition was fulfilled when at least two of the following criteria were met within 48 hours from the intervention: Leucocyte count >12.0 or <4.0x10⁹/l, respiratory rate >20 breaths per minute or PaCO₂ ≤4.3 kPa/32 mmHg, heart rate >90 bpm and temperature >38.0°C or <36.0°C. The primary endpoint was 3-years all-cause mortality. 

Results: 49.7% (185/373) of the patients after MV-TEER developed SIRS (Figure). Patients with NYHA class III/IV experienced SIRS more frequently (SIRS 82.4% (149/185), no SIRS 79% (147/188); p=0.029). Patients that developed SIRS spent more days on ICU (SIRS: 1.00 [1.00, 2.00] vs. no SIRS: 1.00 [1.00, 1.00]; p<0.001) and overall length of stay in hospital was longer (SIRS: 3.00 [3.00, 5.00] vs. no SIRS:  3.00 [3.00, 4.00]; p<0.001) compared to patients without SIRS. All-cause mortality at 3 years was 33.5% (125/373) in the studied population. Patients with SIRS after MV-TEER had a higher 3-years mortality (HR 1.49, [95% CI: 1.04, 2.13]; p=0.0264) compared to patients without SIRS (SIRS: 38.9% (72/185) vs. SIRS: 28.2% (53/188); p=0.03) (Figure). The development of SIRS (HR 2.03 [95% CI: 1.03, 3.97]; p=0.03863), diabetes (HR 2.90 [95% CI: 1.36, 6.21]; p=0.00578), and previous stroke/TIA (HR 1.55 [95% CI: 1.02, 2.34]; p=0.03612) were identified as independent risk factors for 3-years all-cause mortality, whereas female gender (HR 0.46 [95% CI: 0.22, 0.96]; p=0.03989) and previous carotid stenosis (HR 0.37 [95% CI: 1.29, 11.16]; p=0.01535) showed a lower risk for 3-years all-cause mortality.

Conclusions: The incidence of SIRS after MV-TEER is high, affecting approximately half of the patients. Occurrence of SIRS prolongs patients in-hospital stay and was associated with an increased 3-years all-cause mortality. 

Figure