In-hospital percutaneous coronary intervention improves in-hospital survival in patients with acute inferior myocardial infarction particularly with right ventricular involvement.

OBJECTIVE: Assess the interaction between fibrinolysis and in-hospital percutaneous coronary intervention (PCI) in patients with inferior myocardial infarction (MI), particularly those with electrocardiographic evidence of right ventricular infarction (RVI). DESIGN: Retrospective observational study. PATIENTS: Consecutive patients with inferior MI identified from an MI registry between January 1998 and January 2004. INTERVENTIONS: Propensity analyses and multiple regression analysis were used to determine the mortality benefit of PCI. MAIN OUTCOME MEASURES: In-hospital morbidity and mortality. RESULTS: In total, 465 patients with inferior MI received fibrinolytic therapy (median pain-to-needle time of 167 minutes; IQR 100-311 minutes). The main predictors of PCI were recurrent chest pain, peak creatine kinase, age, reinfarction, presence of heart failure and male gender. Significant independent predictors of in-hospital mortality were age > or = 75 years, RVI, initial systolic blood pressure < or = 80 mmHg, female gender and no in-hospital PCI. In-hospital PCI was performed in 184/465 (40%) patients; 55 (30%) had rescue PCI performed < or = 6 hours post fibrinolysis, 45 (24%) within 6-24 hours and 84 (46%) > or = 24 hours. In-hospital PCI was associated with reduced in-hospital mortality (PCI: 9 [5%] vs. no PCI: 40 [14%]; p < 0.001) mainly in those with RVI (PCI: 8 [8%] vs. no PCI 33 [23%]; p = 0.002) compared with no RVI (PCI: 1 [1%] vs. no PCI 7 [5%]; p = 0.1). CONCLUSION: A strategy of timely fibrinolysis combined with in-hospital PCI including rescue PCI may result in a significant reduction in in-hospital mortality and morbidity in patients with inferior MI, particularly those with RVI.

Activation patterns during selective pacing of the left ventricle can be characterized using noninvasive electrocardiographic imaging.

BACKGROUND: Noncontact endocardial mapping allows accurate beat-to-beat reconstruction of the reentrant pathway of ventricular tachycardia and improves outcomes after ablation. Several studies support electrocardiographic imaging (ECGI) as a means of noninvasively outlining epicardial activation despite constraints of internal geometry. However, few have explored its clinical application. This study aims to evaluate ECGI during selective left ventricular (LV) pacing, relative to an invasive approach. METHODS: Multisite pacing was performed within the left ventricles of 3 patients undergoing invasive procedures. Simultaneous recording of endocardial potentials using a noncontact multielectrode array and body surface potentials (BSP) using an 80-electrode torso vest was performed. A total of 16 recordings were made. The inverse solution was applied to BSP to reconstruct epicardial activation. Single-paced beats from real and virtual electrograms were used to construct 3-dimensional isochronal and isopotential maps. Endocardial and epicardial data were then superimposed onto a single geometry to allow quantitative comparison of activation foci. RESULTS: Good correlation was observed between endocardial activation patterns and those reconstructed from BSP using ECGI. This was repeatedly demonstrated in all LV regions except for the septum (3 recordings). Epicardial isochronal maps were able to locate early and late activation to mean distances of 13.8 +/- 4.7 and 12.5 +/- 3.7 mm from endocardial data. Isopotential maps localized pacing sites with comparable accuracy (14 +/- 5.3 mm). CONCLUSIONS: Body surface potentials and reconstructed epicardial activation patterns during LV pacing correlate well with endocardial data acquired invasively. The exception was during pacing of the septum. Although early results are encouraging, further quantitative data are required to fully validate and apply this noninvasive tool in the clinical arena.