Abstract
Background
The presence of cardiogenic shock (CS) after ST-elevation acute myocardial infarction (STEMI) is associated with a high mortality. Traditionally, severe left ventricular dysfunction is assumed to be the main predictor of CS, however trials and registries show that in average left ventricular function is only moderately depressed in CS after acute myocardial infarction.
Purpose
To characterize the population of patients (Pts) with CS after STEMI but without severe left ventricular dysfunction and assess their impact in mortality.
Methods
From a national multicenter registry, we evaluated 7181 Pts with STEMI and ejection fraction (EF) >30%, and excluded all pts with STEMI and an EF<30%. We considered 2 groups: Group 1 – Pts who developed CS and Group 2 - Pts who didn't developed CS. We registered age, gender, cardiovascular and non-cardiovascular co-morbidities, electrocardiographic presentation, vital signs at admission, reperfusion strategies, reperfusion times and coronary anatomy. We evaluated the following in-hospital complications: Re-Infarction, mechanical complications, high-grade atrial ventricular block, sustained ventricular tachycardia (VT) atrial fibrillation (AF) and stroke. We compared the in-hospital mortality.
Results
The presence of CS without severe left ventricular dysfunction was observed in 5,2% pts (n=376), being CS present at admission in 51,2% of these pts. The mean EF was lower in group 1 pts (44% ± 11 vs 51±11%, p<0,001). Patients in group 1 were older (70±14 vs 63±13 years, p<0,001), more females (39,4% vs 23,3%, p<0,001), had a higher prevalence of previous valvular heart disease (2,7% vs 1,0%, p=0,005), heart failure (4,8% vs 1,4%, p<0,001, peripheral artery disease (5,5% vs 2,9%, p=0,004), chronic kidney disease (6,4% vs 2,7%, p<0,001) and chronic pulmonary obstructive disease (8,2% vs 3,1%, p<0,001). At admission, Group 1 pts had more atrial fibrillation (10,4% vs 4,4%, p<0,001) and received less reperfusion (77,7% vs 83,0%, p=0,008), without differences in the type of reperfusion or times to reperfusion. The presence of multivessel disease (60,0% vs 45,7%, p<0,001) and left main disease (6,6% vs 2,4%, p<0,001) were more prevalent in Group 1 pts. Group 1 pts had more in-hospital complications: Re-Infarction (3,5% vs 0,7%, p<0,001), AF (22,1% vs 5,0%, p<0,001), mechanical complications (9,6% vs 0,5%, p<0,001), high atrial ventricular block (26,7% vs 3,7%, p<0,001), VT (10,6% vs 1,9%, p<0,001), stroke (1,9% vs 0,6%, p=0,01) and major bleeding (10,4% vs 1,5%, p<0,001). In-hospital mortality was much higher in Group 1 pts (26,6% vs 1,4%, p<0,001).
Conclusions
Cardiogenic shock is present in 5,2% of STEMI pts without severe ventricular dysfunction. These pts were older, more frequent female, had higher morbidities and in-hospital complications. Even without severe ventricular dysfunction, cardiogenic shock in these patients was associated with much higher in-hospital mortality.
Letter by Ehdaie and Rubin Regarding Article, “Long-Term Arrhythmia-Free Survival in Patients With Severe Left Ventricular Dysfunction and No Inducible Ventricular Tachycardia After Myocardial Infarction”
