Objectives: To evaluate the frequency and the factors associated with performance of echocardiography in acute coronary syndrome (ACS) patients during their stay in intensive care units or coronary care units (ICU/CCU).
Methods: Retrospective cohort study including all patients diagnosed with acute coronary syndrome-unstable angina (UA), acute myocardial infarction (AMI)-included in the 'ARIAM' Spanish multi-centre register. The study period was from June 1996 to December 2005. The follow-up period is limited to the time of stay in the Intensive Care Units or Coronary Care Units (ICUs/CCUs). A univariate analysis was carried out on the patients with UA and AMI according to whether or not echocardiograms were performed during their stay in ICU/CCU. In addition the data was evaluated for any temporal variation in the performance of echocardiography, and two multivariate analyses were carried out to evaluate the factors associated with performance of echocardiography in UA and AMI patients.
Results: The study period included 45,688 AMI patients and 17,277 UA patients. Echocardiograms were performed in 26.87% AMI patients and 16.75% UA patients. In total, 15,172 echocardiograms were performed in ACS patients (23.6%). The multivariate analysis demonstrated that the variables associated with the performance of echocardiography in UA were: Killip and Kimball class, cigarette smoking, family history of cardiovascular events, cardiogenic shock, uncontrolled angina, mechanical ventilation and treatment with ACE inhibitors, while the presence of previous AMI was associated with fewer echocardiograms being performed. In AMI, the multivariate analysis showed the following variables to be associated with the performance of echocardiography: Killip and Kimball class, Q-AMI, right heart failure, the need for insertion of Swan-Ganz catheter, cardiogenic shock, high-degree AV block and the administration of ACE inhibitors, while age was associated with fewer being performed. Over the 10 years of the study period, there was a discrete but significant increase in the use of echocardiography in patients in ICU/CCU.
Conclusions: Echocardiography is not commonly used in ACS patients while in ICU/CCU. UA and AMI patients who did have echocardiograms during their stay in ICU/CCU were chiefly those presenting heart failure and major complications, and represent a subpopulation with poor prognosis. The performance of echocardiography in ACS patients increased slightly over the length of their stay in ICU/CCU.