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Purpose: Following corrective surgery for tetralogy of Fallot (TOF), approximately one-third of these patients develop low cardiac output (CO) due to right ventricular (RV) diastolic heart failure. Extubation is beneficial in these patients because the fall in intrathoracic pressure that occurs with conversion from positive pressure breathing to spontaneous breathing improves venous return, RV filling and CO. We hypothesized that if CO were to increase but remain limited following extubation, the obligatory increase in perfusion to the respiratory pump that occurs with loading of the respiratory musculature may occur at the expense of other vital organs, including the brain., Materials and Methods: We conducted a retrospective analysis of all patients undergoing repair of TOF and monitoring of cerebral oxygenation using near infrared spectroscopy. We evaluated the following parameters two hours prior to and following extubation: mean and systolic arterial blood pressure (MBP, SBP), right atrial pressure (RAP), heart rate (HR) and cerebral oxygenation., Results: The study included 22 patients. With extubation, MBP and SBP increased significantly from 67.3 ± 6.5 to 71.1 ± 8.4 mm Hg (P= 0.004) and from 87.2 ± 8.6 to 95.9 ± 10.9 mm Hg (P= 0.001), respectively, while the HR remained unchanged (145 vs. 146 bpm). The RAP remained unchanged following extubation (11.9 vs. 12.0 mm Hg). Following extubation, cerebral oxygen saturations increased significantly from 68.5 ± 8.4 to 74.2 ± 7.9% (P < 0.0001). Cerebral oxygen saturations increased by ≥5% in 11 of 22 patients and by ≥10% in 5 of 22 patients., Conclusion: We conclude that converting from positive pressure ventilation to spontaneous negative pressure breathing following repair of TOF significantly improves arterial blood pressure and cerebral oxygenation.

The effectiveness of heart failure management in clinical practice is limited by physicians' suboptimal utilization of effective medications, patients' poor adherence to dietary sodium limitation and optimal drug therapy, and the lack of systematic monitoring of patients after hospitalization. The present study evaluated the feasibility and safety of MULTIFIT, a physician-supervised, nurse-mediated, home-based system for heart failure management that implements consensus guidelines for pharmacologic and dietary therapy using a nurse manager to enhance dietary and pharmacologic adherence and to monitor clinical status by frequent telephone contact. Fifty-one patients with the clinical diagnosis of heart failure were followed for 138 +/- 44 days. Daily dietary sodium intake fell by 38%, from 3,393 to 2,088 mg (p = 0.0001); average daily medication doses increased significantly (lisinopril: 17 to 23 mg, p <0.001; hydralazine: 140 to 252 mg, p = 0.01). Functional status and exercise capacity improved significantly (p = 0.01). Compared with the 6 months before enrollment and normalized for variable follow-up, the frequency of general medical and cardiology visits declined by 23% and 31%, respectively (both p <0.03); emergency room visits for heart failure and for all causes declined 67% and 53%, respectively (both p <0.001). Hospitalization rates for heart failure and for all causes declined 87% and 74%, respectively (p = 0.001), compared with the year before enrollment. The MULTIFIT system enhanced the effectiveness of pharmacologic and dietary therapy for heart failure in clinical practice, improving clinical outcomes and reducing medical resource utilization.