Background Acute coronary syndromes (ACS) are a major cause of mortality and morbidity in the developed world. By 2020, ACS will be the leading cause of morbidity and mortality worldwide, largely due to substantial increases in ACS burden in developing countries. The developing world has been under-represented in international ACS registries. The Arabian Gulf area is a part of the developing world where little is known about the epidemiology of ACS. The first aim of the dissertation is to compare ACS patient characteristics, current practice patterns, and in-hospital outcomes in the Arabian Gulf area to a large multinational sample. Patients with an ACS suffer numerous clinical complications that worsen their prognosis. Cardiogenic shock (CS) is the most serious complication of ACS and the leading cause of in-hospital death. Despite advances in therapies; CS hospital mortality rates continue to exceed 50%. The second aim of the dissertation is to describe the characteristics of patients presenting with ACS complicated by cardiogenic shock, their management, and outcomes in a large multinational sample.
In recent years, ACS has been increasingly affecting younger patients. While marked age-related differences have been observed in the risk of developing as well as the prognosis of ACS, few studies however examined time trends in the epidemiology of ACS in young adult patients. The third aim of the dissertation is to examine trends in frequency rates, patient characteristics, treatment practices, and outcomes in young adults hospitalized with an ACS.
Methods Data from two large multinational registries of patients hospitalized with an ACS were used for this investigation. Nearly 65,000 patients were enrolled in the Global Registry of Acute Coronary Events (GRACE) between 2000 and 2007, while 6,700 patients participated in the Gulf Registry of Acute Coronary Events (Gulf RACE) in 2007.
Results Aim1: Patients in Gulf RACE were significantly younger and were more likely to be male, diabetic, and smoke Compared to GRACE. Patients in Gulf RACE were less likely to receive evidence based therapies. Short-term mortality rates were comparable between the two patient cohorts. Aim2: Compared to patients with no CS, patients with CS were more likely to be older, female, have a history of diabetes, and heart failure. Patients with CS were less likely to receive effective cardiac catheterization and adjunctive cardiac medications. In-hospital case-fatality rate of patients with CS were 59.4%. While in-hospital mortality declines over the study period, incidence rates only showed minor declines. Aim2: Baseline characteristics of patients \u3c 55 years of age did not significantly change, while the use of evidence based therapies increased significantly during the years under study. Rates of short-term adverse outcomes and mortality significantly declined over time.
Conclusions We observed marked regional differences in the risk profile, clinical management, and outcomes of patients with an ACS internationally compared to the Arab Middle East. Despite the encouraging trends in the use of evidence based therapies which have likely contributed to the improving trends in the prognosis of ACS, rates of development of ACS, as well as mortality due to ACS complications, remain high
