Predictors of Obstructive Coronary Disease and Mortality in Adults Having Cardiac Arrest

Coronary Angiography in Patients With Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation on Electrocardiograms: A Comprehensive Review

Out-of-hospital cardiac arrest (OHCA) is among the most common causes of death in the United States. Early coronary angiography (CAG) and percutaneous coronary intervention (PCI) have been associated with improved long-term outcomes in patients with ST-segment elevation (STE) on prearrest or postarrest electrocardiograms. However, data on the utility of catheterization and PCI for improving outcomes after OHCA in patients without STE on electrocardiograms are heterogeneous, with variable results. Although older data have suggested that there is a benefit, recent randomized controlled trials have demonstrated that performing early CAG in patients with OHCA without STE on electrocardiograms may not improve outcomes. In recognition that neurologic devastation and multiorgan failure are common in these patients, physicians face the challenge of selecting appropriate patients for cardiac catheterization and PCI. This review aims to summarize the current data on this topic, with the goal to guide decision making regarding the timing and appropriateness of CAG in patients with OHCA without STE on electrocardiograms, utilizing an evidence-based approach to streamline the patient selection process.

Coronary Angiography in Patients With Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation: A Systematic Review and Meta-Analysis

OBJECTIVES

The authors conducted a meta-analysis to study clinical outcomes in patients who underwent early versus nonearly coronary angiography (CAG) in the setting of out-of-hospital cardiac arrest (OHCA) without ST-segment elevation.

BACKGROUND

The benefit of performing early CAG in patients with OHCA without STE remains disputed.

METHODS

MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines from inception until February 21, 2020. Early and nonearly CAG patients were identified on the basis of the definitions mentioned in respective published studies. The primary outcome studied was 30-day mortality. Secondary outcomes were neurological status and the rate of percutaneous coronary intervention (PCI) following cardiac arrest.

RESULTS

Of 4,516 references, 11 studies enrolling 3,581 patients were included in the final meta-analysis. Random-effects analysis showed no differences in 30-day mortality (risk ratio [RR]: 0.86; 95% confidence interval [CI]: 0.71 to 1.04; p = 0.12; I² = 74%), neurological status (RR: 1.08; 95% CI: 0.94 to 1.24; p = 0.28; I² = 69%), and rate of PCI (RR: 1.22; 95% CI: 0.94 to 1.59; p = 0.13; I² = 67%) between the 2 groups. Diabetes mellitus, chronic renal failure, previous PCI, and lactate level were found to be significant predictors of 30-day mortality on meta-regression (p < 0.05).

CONCLUSIONS

This analysis shows that there is no significant difference in 30-day mortality, neurological status, or rate of PCI among patients with OHCA without STE treated with early versus nonearly CAG. Thirty-day mortality is determined by presentation comorbidities rather than revascularization.

Comorbid CAD and ventricular hypertrophy compromise the perfusion of myocardial tissue at subcritical stenosis of epicardial coronaries

BACKGROUND

Most studies of CAD revascularization have been based on and reported according to angiographic criteria which do not consider the relation between the resulting effective flow distal to the stenosis and the demand of a hypertrophied myocardial tissue.

RESULTS

A mathematical model of the myocardial perfusion in comorbid CAD and ventricular hypertrophy, using Poiseuille's law, indicates that the affected patients are more sensitive to CAD-related hemodynamic changes. They are more prone to develop ischemic complications, mainly non-ST-elevation myocardial infarction (NSTEMI), and arrhythmias than their peers with isolated CAD regarding the same degree of coronary stenosis.

CONCLUSION

Patients with comorbid CAD and ventricular hypertrophy suffer from myocardial hypoperfusion at subcritical epicardial stenosis. Accordingly, the comorbidity of both diseases should be considered upon designing of the treatment regimen.