Background and aim of the study: The study aim was to monitor serum troponin and plasma lactate concentrations in conventional aortic valve replacement compared to a beating-heart technique, perfused via the coronary sinus.

Methods: In this prospective, non-randomized study, which was conducted between 2003 and 2009, a total of 35 patients was allocated to two groups, based on the method of myocardial protection. The groups did not differ significantly in terms of preoperative parameters. Levels of lactate were measured in all 35 patients, and of troponin I in 20 patients, in consecutive samples during and after surgery.

Results: There was no in-hospital mortality and no serious complications among patients. The cardiopulmonary bypass and aortic cross-clamp times were each significantly shorter and lactate and troponin I concentrations higher, in the beating-heart group. No perioperative myocardial infarction was observed.

Conclusion: Although good clinical results were observed in patients operated when using the beating-heart technique with retrograde coronary sinus perfusion, postoperative serum levels of troponin I were higher than in patients operated on using a conventional technique. Although troponin I is considered a prognostic factor for postoperative mortality, this parameter applies only to selected patients rather than for widespread use.

Background and aim of the study: Pulmonary hypertension frequently complicates mitral stenosis, with a subset of these patients exhibiting pressures well in excess of their mitral valve hemodynamics. The prevalence of this condition and its impact on clinical outcome following percutaneous balloon mitral commissurotomy (PBMC) is unknown.

Methods: The transpulmonary gradient (TPG) was measured in 317 patients undergoing PBMC; patients were subsequently defined as having either an appropriate or excessive TPG (< or =15 mmHg or >15 mmHg, respectively). Twenty-two patients were excluded due to valvuloplasty-related significant mitral regurgitation. The remaining 295 patients (250 females, 45 males; mean age 52 +/- 13 years) were prospectively followed up, with each patient underwent serial echocardiography.

Results: Among the patients, 214 (73%) had pulmonary hypertension (pulmonary artery pressure >25 mmHg) and 55 (19%) also had an elevated TPG. Females were almost fivefold more likely than males to have an elevated TPG (p = 0.003). Patients with an elevated TPG had a worse mean NYHA functional class than those with a normal TPG (3.0 +/- 0.5 versus 2.7 +/- 0.6, p = 0.01), while the mitral valve area (MVA) was slightly smaller in patients with an elevated TPG (1.0 +/- 0.2 versus 1.1 +/- 0.2 cm2, p = 0.003). All patients demonstrated a significant increase in MVA after commissurotomy (final MVA 1.7 +/- 0.6 cm2, p < 0.001 for elevated TPG; 1.8 +/- 0.4 cm2, p < 0.001 for normal TPG), and the NYHA class at six months was improved for all patients (2.8 +/- 0.6 versus 1.6 +/- 0.7, p < 0.001). The improvements in NYHA class, TPG and MVA were sustained at 36 months.

Conclusion: Pulmonary hypertension with elevated TPG occurs in patients with mitral stenosis, and is significantly more common in females. Despite worse symptoms and higher right-sided pressures, PBMC is equally successful in patients with a normal TPG, and provides sustained benefit for up to 36 months after the procedure.

Background and aim of the study: The mitral annulus mechanics associated with annular dilation in pathologies such as mitral valve (MV) prolapse, ischemic and dilative heart diseases remain unknown. The study aim was to investigate annulus tension (AT) in the dilated annulus and in the displaced papillary muscles due to these pathological conditions.

Methods: Ten porcine MVs were harvested and mounted on a MV closure test rig with the papillary muscles held in the slack, normal, and taut positions. The MV annulus tissue rested on top of a plastic ring on which it could slide freely. The annulus was held by strings in the periphery during valve closure under hydrostatic trans-mitral pressure. The string tensions were measured, and further divided by string spacing to obtain the AT. Three annuli of normal, 25% dilated and 50% dilated annulus sizes were used.

Results: The AT was lowest at the commissural segment of the annulus, but increased towards the anterior and posterior segments, with a greater increase towards the anterior segment than towards the posterior. The AT increased with the increase of the apical PM displacement from the slack to normal, and then taut position in the commissural segment of the annulus. Although the AT increased with annulus area, the increase was less pronounced in the commissural segment than in the anterior and posterior segments.

Conclusion: There is a significant difference in AT values between a normal and prolapsed MV, and between a normal MV and a MV with displaced papillary muscles. This difference suggests that annular dilation is a consequence and MV counteraction of imbalanced annular mechanics between the AT and myocardial force.

Background and aim of the study: Down-sized ring annuloplasty has been shown to induce left ventricular remodeling in patients with functional ischemic mitral regurgitation (FIMR). To determine if this remodeling comprised papillary muscle (PM) relocation, a chronic FIMR porcine model was used to assess the impact on three-dimensional (3D) PM positioning, by implanting a down-sized rigid ring annuloplasty.

Methods: Six out of ten FIMR pigs that underwent a down-sized mitral ring annuloplasty (CE Classic size 26-28) survived for six weeks postoperatively. 3D cardiac magnetic resonance imaging was carried out at one week preoperatively, and repeated at one and six weeks postoperatively, to assess the direct distances (in mm) from the anterior papillary muscle (APM) and posterior papillary muscle (PPM) to each trigone. Three reference planes were also constructed to determine APM and PPM displacement in the lateral, anterioposterior, and apical directions.

Results: Relative to the preoperative situation, at one week postoperatively a reduced displacement of the APM was observed in an anterior direction (from 18.8 to 16.2 mm; p < 0.05) and from the posterior trigone (from 40.5 to 37.4 mm; p < 0.05) at end-diastole. Relative to one week postoperatively, at six weeks postoperatively a reduced PPM displacement was observed from the anterior trigone (43.0 versus 42.0 mm; p < 0.05) at end-systole. Relative to the preoperative situation, no overall tendency of surgically induced PM relocation was observed at one or six weeks postoperatively.

Conclusion: A down-sized ring annuloplasty did not induce an overall pattern of PM relocation in pigs with chronic FIMR.

Background and aim of the study: Risk models of cardiac valve surgery using a large database are useful for improving surgical quality. In order to obtain accurate, high-quality assessments of surgical outcome, each geographic area should maintain its own database. The study aim was to collect Japanese data and to prepare a risk stratification of cardiac valve procedures, using the Japan Adult Cardiovascular Surgery Database (JACVSD).

Methods: A total of 6562 valve procedure records from 97 participating sites throughout Japan was analyzed, using a data entry form with 255 variables that was sent to the JACVSD office from a web-based data collection system. The statistical model was constructed using multiple logistic regression. Model discrimination was tested using the area under the receiver operating characteristic curve (C-index). The model calibration was tested using the Hosmer-Lemeshow (H-L) test.

Results: Among 6562 operated cases, 15% had diabetes mellitus, 5% were urgent, and 12% involved preoperative renal failure. The observed 30-day and operative mortality rates were 2.9% and 4.0%, respectively. Significant variables with high odds ratios included emergent or salvage status (3.83), reoperation (3.43), and left ventricular dysfunction (3.01). The H-L test and C-index values for 30-day mortality were satisfactory (0.44 and 0.80, respectively).

Conclusion: The results obtained in Japan were at least as good as those reported elsewhere. The performance of this risk model also matched that of the STS National Adult Cardiac Database and the European Society Database.

Background and aim of the study: To date, the natural history of the unicuspid aortic valve (UAV) has been poorly described in the literature. To study the association between UAV with associated cardiac and extracardiac abnormalities, a systematic review was conducted.

Methods: A computerized search was conducted of the medical literature published between 1st January 1966 and 1st September 2008, using the databases MEDLINE, EMBASE, Web of Science and Cochrane database.

Results: Nine articles with 60 pediatric cases (age <15 years) were identified. The mean age at diagnosis was 14 months, the most common presentation of UAV was congestive heart failure due to congenital aortic stenosis, and the most common lesion was isolated aortic stenosis, reported in 19 cases (32%). Associated anomalies included 22 cases (37%) of aortic coarctation, seven (12%) with ventricular septal defect (VSD), three (5%) with patent ductus arteriosus (PDA), and three (5%) with aortic aneurysm. The preoperative diagnosis of UAV was rare, and 33 cases (55%) of pediatric UAV were reported at autopsy or at pathological examination of the surgically excised valves. A total of 26 cases (43%) was treated with either balloon valvoplasty or surgical valvotomy or commissurotomy.

Conclusion: UAV shares many of the features of bicuspid aortic valve, including valvular dysfunction, aortic dilatation, aortic dissection, and dystrophic calcification. The importance of an early diagnosis of UAV lies in its risk of sudden cardiac death and association with other congenital anomalies, such as PDA, VSD, anomalous coronary arteries, and coarctation of the aorta. Further investigations of UAV are warranted in the pediatric age group with regards to familial incidence, associated aortic histopathological changes, the ideal follow up to monitor complications, and surgical intervention.