Predictors of worse outcome after postponing non-emergency cardiac interventions during the COVID-19 pandemic

OBJECTIVE

Deferral of non-emergency cardiac procedures is associated with increased early emergency cardiovascular hospitalisation. This study aimed to identify predictors of worse clinical outcome after deferral of non-emergency cardiovascular interventions.

METHODS

This observational case-control study included consecutive patients whose non-emergency cardiac intervention has been postponed during COVID-19-related lockdown between 19 March and 30 April 2020 (n=193). Cox regression was performed to identify predictors of the combined 1-year end point emergency cardiovascular hospitalisation and death. All patients undergoing non-emergency interventions in the corresponding time period 2019 served as control group (n=216).

RESULTS

The combined end point of death and emergency cardiovascular hospitalisation occurred in 70 (36.3%) of 193 patients with a postponed cardiovascular intervention. The planned intervention was deferred by a median of 23 (19-36) days. Arterial hypertension (HR 2.27; 95% CI 1.00 to 5.12; p=0.049), chronic kidney disease (HR 1.89; 95% CI 1.03 to 3.49; p=0.041) as well as severe valvular heart disease (HR 3.08; 95% CI 1.68 to 5.64; p<0.001) were independent predictors of death or emergency hospitalisation. Kaplan-Maier estimators of the combined end point were 31% in patients with arterial hypertension, 56% in patients with severe valvular heart disease and 77% with both risk factors (HR 12.4, 95% CI 3.8 to 40.7; p<0.001) and only 9% in patients without these risk factors (log rank p<0.001). N-terminal pro-B-type natriuretic peptide (NT-proBNP) cut-point of ≥1109 pg/mL best predicts the occurrence of primary end point event in deferred patients (area under the curve 0.71; p<0.001; sensitivity 63.8%, specificity 69.4%).

CONCLUSION

Our results suggest that patients with either arterial hypertension, chronic kidney or severe valvular heart disease are at very high risk for emergency hospitalisation and increased mortality in case of postponed cardiac interventions even in supposed stable clinical status. Risk seems to be even higher in patients suffering from a combination of these conditions. If the ongoing or future pandemics force hospitals again to postpone cardiac interventions, the biomarker NT-proBNP is an applicable parameter for outpatient monitoring to identify those at risk for adverse cardiovascular events.

Sphingosine-1-Phosphate Attenuates Lipopolysaccharide-Induced Pericyte Loss via Activation of Rho-A and MRTF-A

The high mortality seen in sepsis is caused by a systemic hypotension in part owing to a drastic increase in vascular permeability accompanied by a loss of pericytes. As has been shown previously, pericyte retention in the perivascular niche during sepsis can enhance the integrity of the vasculature and promote survival via recruitment of adhesion proteins such as VE-cadherin and N-cadherin. Sphingosine-1-phosphate (S1P) represents a lipid mediator regulating the deposition of the crucial adhesion molecule VE-cadherin at sites of interendothelial adherens junctions and of N-cadherin at endothelial-pericyte adherens junctions. Furthermore, in septic patients, S1P plasma levels are decreased and correlate with mortality in an indirectly proportional way. In the present study, we investigated the potential of S1P to ameliorate a lipopolysaccharide-induced septic hypercirculation in mice. Here we establish S1P as an antagonist of pericyte loss, vascular hyperpermeability, and systemic hypotension, resulting in an increased survival in mice. During sepsis S1P preserved VE-cadherin and N-cadherin deposition, mediated by a reduction of Src and cadherin phosphorylation. At least in part, this effect is mediated by a reduction of globular actin and a subsequent increase in nuclear translocation of MRTF-A (myocardin-related transcription factor A). These findings indicate that S1P may counteract pericyte loss and microvessel disassembly during sepsis and additionally emphasize the importance of pericyte-endothelial interactions to stabilize the vasculature.