Henry Ooi

Benefits of ambulatory axillary intra-aortic balloon pump for circulatory support as bridge to heart transplant.

OBJECTIVE Axillary intra-aortic balloon pump therapy has been described as a bridge to transplant. Advantages over femoral intra-aortic balloon pump therapy include reduced incidence of infection and enhanced patient mobility. We identified the patients who would benefit most from this therapy while awaiting heart transplantation. METHODS We conducted a single-center, retrospective observational study to evaluate outcomes from axillary intra-aortic balloon pump therapy. These included hemodynamic parameters, duration of support, and success in bridging to transplant. We selected patients on the basis of history of sternotomy, elevated panel-reactive antibody, and small body habitus. Patients were made to ambulate aggressively beginning on postoperative day 1. RESULTS Between September 2007 and September 2010, 18 patients underwent axillary intra-aortic balloon pump therapy. All patients had the devices placed through the left axillary artery with a Hemashield side graft (Boston Scientific, Natick, Mass). Before axillary placement, patients underwent femoral placement to demonstrate hemodynamic benefit. Duration of support ranged from 5 to 63 days (median = 19 days). There was marked improvement in ambulatory potential and hemodynamic parameters, with minimal blood transfusion requirements. There were no device-related infections. Some 72% of the patients (13/18) were successfully bridged to transplantation. CONCLUSIONS Axillary intra-aortic balloon pump therapy provides excellent support for selected patients as a bridge to transplant. The majority of the patients were successfully bridged to transplant and discharged. Although this therapy has been described in previous studies, this is the largest series to incorporate a regimen of aggressive ambulation with daily measurements of distances walked.

Timing of Left Ventricular Remodeling in Nonischemic Dilated Cardiomyopathy

Background: Mineralocorticoid receptor antagonist (MRA) treatment produces beneficial left ventricular (LV) remodeling in nonischemic dilated cardiomyopathy (NIDCM). This study addressed the timing of maximal beneficial LV remodeling in NIDCM when adding MRA. Materials and Methods: We studied 12 patients with NIDCM on stable &bgr;‐blocker and angiotensin‐converting enzyme inhibitor/angiotensin receptor‐blocking therapy who underwent cardiac magnetic resonance imaging before and after 6‐31 months of continuous MRA therapy. Results: At baseline, the LV ejection fraction (LVEF) was 24% (19‐27); median [interquartile range]. The LV end‐systolic volume index (LVESVI) was 63 ml (57‐76) and the LV stroke volume index (LVSVI) was 19 ml (14‐21), all depressed. After adding MRA to the HF regimen, the LVEF increased to 47% (42‐52), with a decrease in LVESVI to 36 ml (33‐45) and increase in LVSVI to 36 ml (28‐39) (for each, P < 0 .0001). Using generalized least squares analysis, the maximal beneficial remodeling (defined by maximal increase in LVEF, the maximal decrease in LVESVI and maximal increase in LVSVI) was achieved after approximately 12‐16 months of MRA treatment. Conclusions: Adding MRA to a standard medical regimen for NIDCM resulted in beneficial LV remodeling. The maximal beneficial remodeling was achieved with 12‐16 months of MRA therapy. These results have implications for the timing of other advanced therapies, such as placing internal cardioverter‐defibrillators.