Six-Minute Walk Test Predicts Postoperative Delirium After Transcatheter Aortic Valve Replacement.

OBJECTIVE: This study investigated the incidence and risk factors of postoperative delirium (POD) after transcatheter aortic valve replacement (TAVR) and to evaluate the association between preoperative conditions, particularly frailty, and POD. DESIGN: Observational, case-control study. SETTING: Single-center university hospital. PARTICIPANTS: The study comprised 124 patients who underwent TAVR and were divided into the following two groups: group D (patients diagnosed with POD) and group C (patients without POD). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Twenty-seven patients (21.7%) developed POD (95% confidence interval 14.9%-30.1%). POD was defined as a diagnosis of delirium using the Confusion Assessment Method for Intensive Care Unit scale during the patients' intensive care unit stay. Preoperative and postoperative data of patient characteristics were obtained from their medical records. A multivariate logistic regression analysis was performed using variables associated with POD incidence. Frailty scores were significantly higher in group D than in group C. The distance covered in the six-minute walk test (6MD) was significantly shorter in group D than in group C. The risk of developing POD was significantly higher in patients with a 6MD shorter than 220 m. Multivariate logistic regression analysis showed that a shorter 6MD was an independent risk factor for POD (odds ratio 5.66; p = 0.004). CONCLUSION: In the present study, POD was seen in 21.7% of the patients who underwent TAVR. A 6MD shorter than 220 m was an independent preoperative risk factor for POD. For patients at high risk of POD, more careful management in the perioperative period may reduce POD.

Outcome of non-transplant surgical strategy for end-stage dilated cardiomyopathy in young children.

BACKGROUND: The shortage of heart transplantation donors is a problem, but partial left ventriculectomy (PLV) and mitral valve replacement (MVR) are feasible at the optimal timing, even in young children. METHODS AND RESULTS: From May 1998 to May 2008, 11 children under the age of 3 years were diagnosed with severe dilated cardiomyopathy (DCM). Indications and outcomes of non-transplant surgical strategies were evaluated and 8 procedures were performed in 6 children: 5 PLV and 3 MVR. Two of them underwent MVR after PLV because of deterioration of mitral regurgitation (MR). Age at surgery ranged from 8 months to 2 years 11 months. Four are alive, of whom 1 eventually underwent a heart transplant overseas. Two children died during the study period: 1 who underwent only MVR died of intracranial bleeding during thrombolytic therapy for a thrombus stack valve and the other child died of congestive heart failure because of progressive MR 2 months after PLV. Follow-up after PLV ranged from 2 months to 8 years, and after MVR ranged from 1 month to 4 years. CONCLUSIONS: PLV and MVR are feasible and effective and should be considered when heart failure resists conventional therapy.

A porcine model of ischemic heart failure produced by chronic placement of a tube in a coronary artery.

BACKGROUND AND AIMS: Animal models of heart failure (HF) are useful to clarify the mechanism and to develop therapeutic interventions. To produce an easy ischemic HF model, we induced myocardial infarction (MI) in pigs by placing a tube in the coronary artery. METHODS: Twelve pigs underwent echocardiography and were randomly allocated to the myocardial infarction group (MI group) and the control group. In the MI pigs, a 4.2 F nylon tube was placed via the carotid artery in the left circumflex coronary (LCx) artery to induce MI. Three months thereafter, thoracotomy was performed in the both groups and left ventricular (LV) pressure-volume relation was evaluated. RESULTS: Body weight, LV dimension and function did not differ in the baseline state between the two groups. Three months after the tube placement, LV diameter was larger (47+/-3 vs. 42+/-2 mm) and its fractional shortening was lower in the MI group than the control group. In addition, aortic flow was decreased, LV ejection fraction was decreased (25+/-5 vs. 52+/-6%) and LV diastolic pressure was elevated (14+/-3 vs. 8+/-2 mmHg) in the MI group compared with the control group. The extent of MI was 26+/-5% of the LV in the MI pigs. CONCLUSION: The method of placing a tube in the coronary artery does not need thoracotomy or an additional procedure and enables the production of an ischemic HF model of pigs.