Drug related adverse events due to cardiotropic agents : Epidemiology and prognosis in the emergency department.

Introduction: The severity of cardiotropic agents overuse is related to the risk of cardiac and hemodynamic life-threatening situations. Toxicity is attributed to their narrow therapeutic spectrum and pharmacodynamic properties. The clinical presentation, however, remains polymorphic and represents a challenge for the emergency physician to relate accountability to the exact agent.

Aim: To evaluate epidemiological, clinical and prognostic profile of patients visiting emergency department in whom iatrogeny secondary to cardiotropic use was diagnosed.

Methods: This was a single-center prospective study over 12 months. We included successively all patients aged over 18 years in whom diagnosis of cardiotropic iatrogeny was made. Cardiotropic related drug-induced events were selected after collegial decision making processing. Prognosis was evaluated in terms of severity and mortality at day 30. Univariate analysis was conducted. P<0.05 was significant.

Results: We enrolled 51 patients. Median age was 72 years with IQR (25,75) of (62,78). Sex ratio was 0.64. Twenty cases of misuse were identified (39%) with 51% of cases being related to the physician. Accountability of the adverse drug event (ADE) was 51%. The ADE was considered severe in 45% of cases and the death rate on day 30 was 12%. Drug classes were dominated by beta-blockers in 20 patients (39%) and anti-arrhythmic agents (Amiodarone ®) in 18 patients (35%). Beta-blockers were significantly the most incriminated in the occurrence of severe ADE. A double iatrogeny was found in 13 patients (25%). Misuse and physician-related ADE were found to be predictive of the severity of ADE in univariate analysis with respectively: For misuse:(OR brut=22, CI95%=[5.2;93.5] ; p<0.001) and for related physician ADE (OR brut = 3,7 ; CI95%=[1.1;12] ; P= 0.015). Predictive factors of mortality at day 30 in the univariate analysis were: Past renal failure : OR brut 5,8; CI95%[1,3-26,5]; p=0,015 ; misuse with OR brut=16.7, 95% CI=[1.9-143.5], p=0.002 and severe ADE with OR brut=15, 95% CI=[1.75-129], p=0.032.

Conclusion: This study showed that ADE related to Cardiotropic agents are frequent and remain a serious condition especially in elderly. Betablockers agents were the mostly incriminated therapeutic class in the severity of the clinical condition by its hemodynamic repercussions responsible of a high rate of hospitalizations and mortality. Misuse and physician-related ADE were found to be predictive of the severity. Whereas, occurrence of severe ADE, misuse and past renal failure were predictive of mortality. Moreover, in 51% patients, ADE was preventable and related to the prescription of physician showing the main role of the preventability and the role of the prescriber in the genesis of this severe condition.