Abstract
Background
Spontaneous Coronary Artery Dissection (SCAD) is an important cause of acute coronary syndrome particularly in young-middle aged women. Revascularisation is challenging due to an underlying disrupted and friable coronary vessel wall leading to widely reported worse outcomes than for atherosclerotic coronary disease. Therefore, a conservative approach where possible is favoured however in some cases haemodynamic instability, ongoing ischaemia and reduced distal flow mandates consideration of revascularisation.
Purpose
To compare SCAD survivors managed with PCI or conservatively in terms of presentation characteristics, complications and long-term outcomes.
Methodology and results
226 angiographically confirmed SCAD survivors (95% female,47±9.7yrs) who underwent PCI were compared in a case control study with two hundred and twenty-five angiographically confirmed SCAD survivors (92% female, 49±9.9yrs) who were conservatively managed. Patients were recruited from UK, Spanish and Dutch SCAD registries and both groups were well matched in terms of baseline demographics.
Those treated with PCI were more likely to present with proximal SCAD (30.8% vs 7.6% P<0.01) and ST elevation myocardial infarction (STEMI) or cardiac arrest with reduced flow (32.3% vs 6.3% P<0.01). Intervention was performed with stents in 72.4%, plain old balloon angioplasty in 21.1% and wiring in 6.4% of cases and more often for multi-segment disease (40.8% vs 26.3% P<0.01). In cases with initial reduced flow undergoing PCI an improvement in flow was seen in 83%.
Analysis of UK PCI cases (n=144) reveal complications in 56 (38.8%). However, when assessed for significance defined by a reduction in flow in a proximal/mid vessel, stent extension into left main stem, iatrogenic dissection requiring PCI and CABG as a consequence of PCI only 13 cases (9%) met criteria. Iatrogenic dissection accounts for the majority (76.9%). SCAD lesion length was associated with presence of complications (P=0.025). There was a non-significant trend towards major adverse cardiovascular events (MACE) occurring more frequently in those undergoing PCI (18% vs 11% P=0.067) driven by revascularisation (5% vs 1% P=0.036). Median follow up was 2.7 years.
Conclusions
PCI in SCAD is often performed in higher risk patients; in those presenting with reduced flow, the majority demonstrate improvement. Importantly whilst overall complication rates were similar to those widely reported, clinically significant complications were low. Multivariate modelling will reveal factors associated with complications to aid future decision making in this challenging patient group.
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): British Heart Foundation
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