Background-The role of QTc interval prolongation in heart failure remains poorly defined. To better understand it, we analyzed the QTc interval duration in patients with heart failure with high B-type natriuretic peptide (BNP) levels and analyzed the combined prognostic impact of prolonged QTc and elevated BNP. Methods and Results-QTc intervals were measured in 241 patients with heart failure who had BNP levels Ͼ400 pg/mL.QT interval duration was determined by averaging 3 consecutive beats through leads II and V 4 on a standard 12-lead ECG and corrected by using the Bazett formula. QTc intervals were prolonged (Ͼ440 ms) in 122 (51%) patients and normal in 119 (49%). The BNP levels in these 2 groups were not significantly different (786Ϯ321 pg/mL in the prolonged QTc group versus 733Ϯ274 pg/mL in the normal QTc group, Pϭ0.13). During 6 months of follow-up, 46 patients died, 9 underwent transplantation, and 17 underwent left ventricular assist device implantation. The deaths were attributed to pump failure (nϭ24, 52%), sudden cardiac death (nϭ18, 39%), or noncardiac causes (nϭ4, 9%). Kaplan-Meier survival rates were 3 times higher in the normal QTc group than in the prolonged QTc group (PϽ0.0001).On multivariate analysis, prolonged QTc interval was an independent predictor of all-cause death (Pϭ0.0001), cardiac death (Pϭ0.0001), sudden cardiac death (Pϭ0.004), and pump failure death (Pϭ0.0006). Conclusions-Prolonged QTc interval is a strong, independent predictor of adverse outcome in patients with heart failure with BNP levels Ͼ400 pg/mL.
The collection of PBSC for transplantation requires repetitive leukapheresis, typically via central venous catheters (CVC). To assess the complications of this procedure, we reviewed 75 consecutive PBSC transplant candidates requiring 554 leukapheresis on a Haemonetics V50 Plus apheresis system. CVC occlusion necessitating thrombolytic therapy or cancellation of the procedure was the most commonly observed complication, occurring among 37 patients on 86 occasions (15.9% of CVC-aided collections). Thrombolytic therapy was successful in 85%. Of the patients, 16% experienced an infectious complication during the PBSC harvesting; chemotherapy mobilization significantly increased this risk, whereas growth factor mobilization was protective (p < 0.02). Hematologic complications including anemia (median postapheresis nadir hemoglobin 8.8 g/dl) and transient thrombocytopenia (median postapheresis nadir 64,000/microliters) required transfusional support among 30.7% and 14.7% of patients, respectively. The use of chemotherapy mobilization was correlated with increased need for support of both red cells and platelets (p < 0.001). Additional complications included catheter placement problems, symptomatic citrate-related hypocalcemia, transient hypotension, and machine-related malfunctions. Although the complications of the PBSC harvests were manageable, given their frequency the decision to pursue this form of hematopoietic rescue in preference to traditional operative bone marrow harvesting must address these risks.
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