Ken Nakamura

High cognitive function of an ALS patient in the totally locked-in state

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by progressive degeneration of upper and lower motor neurons. Patients with ALS progressively lose their ability to control voluntary movements and occasionally enter the totally locked-in state (TLS), in which they cannot move any part of their bodies including the eyes. In this study, we clarified the preserved abilities and reorganization of the motor system of a 73-year-old patient with ALS in the TLS using optical topography, a recently developed extension of near-infrared spectroscopy. The patient performed four cognitive tasks: dichotic listening, covert singing, word fluency, and motor imagery. The bilateral prefrontal and bilateral sensorimotor areas were activated during the two language-related tasks (dichotic listening task and the word fluency), the right prefrontal and sensorimotor areas during the covert singing task, and the right prefrontal and dorsal sensorimotor areas during the motor imagery task. Contralateral sensorimotor activation was not observed in the motor imagery task. These results suggest that cognitive functions can be preserved in ALS in the TLS, with sensorimotor areas playing an important role.

The Impact of Preoperative and Postoperative Pulmonary Hypertension on Long-Term Surgical Outcome after Mitral Valve Repair for Degenerative Mitral Regurgitation

PURPOSE The aim of this study is to elucidate the impact of preoperative and postoperative pulmonary hypertension (PH) on long-term clinical outcomes after mitral valve repair for degenerative mitral regurgitation. METHODS A total of 654 patients who underwent mitral valve repair for degenerative mitral regurgitation between 1991 and 2010 were retrospectively reviewed. Patients were divided into PH(+) group (137 patients) and PH(-) group (517 patients). Follow-up was complete in 99.0%. The median follow-up duration was 7.5 years. RESULTS Patients in PH(+) group were older, more symptomatic and had higher tricuspid regurgitation grade. Thirty-day mortality was not different between 2 groups (p = 0.975). Long-term survival rate was lower in PH(+) group; 10-year survival rate after the operation was 85.2% ± 4.0% in PH(+) group and 89.7% ± 1.8% in PH(-) group (Log-rank, p = 0.019). The incidence of late cardiac events were not different between groups, however, the recurrence of PH was more frequent in PH(+) group. The recurrence of PH had an adverse impact on survival rate, late cardiac events and symptoms. Univariate analysis showed age and preoperative tricuspid regurgitation grade were the predictors of PH recurrence. CONCLUSION Early surgical indication should be advocated for degenerative mitral regurgitation before the progression of pulmonary hypertension and tricuspid regurgitation.

Long-Term Outcomes of Tricuspid Annuloplasty for Functional Tricuspid Regurgitation Associated with Degenerative Mitral Regurgitation: Suture Annuloplasty Versus Ring Annuloplasty Using a Flexible Band

PURPOSE We investigated the long-term outcomes of suture/ring tricuspid valve annuloplasty for functional tricuspid regurgitation associated with degenerative mitral regurgitation. METHODS We retrospectively reviewed patients who underwent flexible ring tricuspid valve annuloplasty (n = 120) or suture tricuspid valve annuloplasty (n = 42) for functional tricuspid regurgitation concomitant with surgery for degenerative mitral regurgitation (mean follow-up duration, 5.3 ± 5.1 years). RESULTS The mean age of patients was 62.5 ± 13.1 years. Thirty-day mortality was zero in the suture group, and 0.8% in the ring group. Tricuspid regurgitation grade at discharge was lower in the ring group ( p = 0.002). No difference was observed between survival and freedom from major cardiac/cerebrovascular adverse events between the groups. However, freedom from ≥moderate tricuspid regurgitation was higher in the ring group (Log-rank p = 0.003). From univariate analysis, the risk factors for ≥moderate TR were suture annuloplasty and preoperative tricuspid regurgitation grade. No reoperation for recurrent tricuspid regurgitation occurred in either group because symptoms experienced by patients with recurrent tricuspid regurgitation were relatively insignificant. CONCLUSION Concomitant tricuspid annuloplasty using flexible bands offered improved durability than suture annuloplasty for preventing postoperative tricuspid regurgitation progression.

Midterm Outcomes of Chordal Cutting in Combination with Downsized Ring Annuloplasty for Ischemic Mitral Regurgitation

PURPOSE We describe midterm outcomes after division of secondary chords (chordal cutting) combined with downsized ring annuloplasty for ischemic mitral regurgitation (IMR). METHODS We compared the clinical outcomes in patients who underwent chordal cutting with downsized ring annuloplasty (CC-group, n = 15) and those who underwent conventional ring annuloplasty only (Conventional-group, n = 35) for IMR. Follow-up was complete in all patients. The median follow-up time was 4.1 years. RESULTS Thirty-day mortality was 0% in CC-group and 20% in Conventional-group. The overall survival rate at 5-year was 80.8% ± 12.6% in CC-group and 61.7% ± 8.4% in Conventional-group (Log-rank, p = 0.145). The freedom rate from valve-related events at 5 year was 84.6% ± 10.0% in CC-group and 65.3% ± 10.1% in Conventional-group (Log-rank, p = 0.213). Recurrence of severe mitral regurgitation was revealed in 3 patients of CC-group. Preoperative tenting height was the significant predictor of mitral regurgitation recurrence. In CC-group, the mean left ventricular ejection fraction was 38.0% ± 14.0%, which was similar to the preoperative value of 40.0% ± 13.2% (p = 0.349). CONCLUSIONS Chordal cutting with downsized ring annuloplasty for IMR is a simple method and provides satisfactory early outcomes. However, it carries with high recurrence of MR especially for patients with high tenting height.

Feasibility and efficacy of mitral valve repair for degenerative mitral regurgitation in the elderly.

PURPOSE The number of elderly patients who require surgical treatment for mitral regurgitation (MR) is increasing. However, the feasibility and efficacy of mitral valve repair in elderly patients are unclear. METHODS We retrospectively reviewed 55 patients, aged ≥75 years, who underwent mitral valve repair for degenerative MR between 1991 and 2011. All patients were followed up for 4.7 ± 3.4 years. RESULTS The patients aged ≥75 years were more symptomatic and had a higher incidence of persistent atrial fibrillation and pulmonary hypertension than those aged <75 years. Thirty-day and in-hospital mortality was 1.8% and 7.3%, respectively, and the 5-year survival rate was 81.6% ± 5.8%. The leading cause of late death was stroke, which primarily occurred in patients with postoperative atrial fibrillation. Except for a single failure of repair due to technical reasons, there was no recurrence of severe MR or reoperation on the mitral valve. In the late follow-up period, the mean left ventricular diastolic diameter significantly decreased and the mean left ventricular ejection fraction was approximately 60%. Most patients had mild symptoms at follow-up. CONCLUSION Mitral valve repair can provide satisfactory early as well as long-term outcomes and can preserve left ventricular function even in the elderly.

Long-Term Outcomes after Mitral Valve Repair for Degenerative Mitral Regurgitation with Persistent Atrial Fibrillation

BACKGROUND Atrial fibrillation (AF) adversely affects surgical outcomes of mitral valve surgery. However, the long-term impact of Maze procedure has not been clear yet. PATIENTS AND METHODS We retrospectively investigated 159 patients who underwent mitral valve repair for degenerative mitral regurgitation with persistent AF between 1991 and 2010. The mean age of patients was 63.1 ± 10.5 years. After we started performing Maze procedure in 2002, 65 patients underwent concomitant Maze procedure. The median follow-up time was 7.5 years. RESULTS There was one operative death (0.63%). The overall survival rate was 91.0 ± 2.6% at 5 years and 79.1 ± 4.7% at 10 years. Survival was significantly better in patients who underwent Maze procedure than those who did not. The rate of freedom from AF in patients who underwent Maze procedure was 86.4 ± 4.5% at 1 year and 81.1 ± 5.6% at 5 years. The freedom rate from stroke was higher in patients who underwent Maze procedure than those who did not. Patients with postoperative AF had larger left ventricular systolic and diastolic diameters at follow-up and higher New York Heart Association functional class than patients without postoperative AF (1.4 ± 0.5 vs. 1.1 ± 0.3, p < 0.001). CONCLUSION Maze procedure can have a positive effect on long-term survival, freedom from stroke, and cardiac function.

Long-Term Outcomes of Mitral Valve Repair with the Duran Flexible Ring

Mitral annuloplasty is a reliable mitral valve repair technique. There are two types of annuloplasy rings: the rigid ring and the flexible ring. This study sought to examine the long‐term results of mitral valve repair using a Duran flexible ring.