[Early Clinical Outcomes of Robotic Mitral Valve Repair;Initial Twenty Cases].

We report the early results of our initial 20 consecutive robotic-assisted mitral valve repairs at our institution. A total of 20 patients (aged 55±10 years, 15 males) underwent robotic assisted mitral repairs by using da Vinci system. Successful mitral valve repairs were done in all cases. All patients received an annuloplasty band. Triangular resection were done in 2 cases and artificial chordae were used in 18 cases. There was no conversion to sternotomy intraoperatively. Three cases needed recross-clamping because of mitral regurgitation, mitral stenosis and the problem of venous canula. Cardiopulmonary bypass time and aortic cross-clamp time were 272±56 minutes, 153±41 minutes. There were no hospital mortality and major complications. Post-pump echocardiograms showed no/trivial mitral regurgitation in all cases. Robotic-assisted mitral valve repairs were done safely and the early results were acceptable in our series.

The scalographic pattern of Morlet continuous wavelet transform can differentiate bileaflet valve function.

The authors have discussed the significance of the Morlet continuous wavelet transform of bileaflet mechanical heart valve (BLMHV) sound for detecting its malfunction: consecutive single patterns on the scalogram alway suggested its malfunction, whereas the tandem pattern with two steepled figures was demonstrated in both normal and malfunctioning valves. Therefore, authors have tried to distinguish this pattern between them by manually calculated multiple scalographic parameters. Although only the sum of wavelet coefficients (SWC) is supposed to be closer to valve sound property than other parameters, its calculation was not available in the original wavelet application. Therefore, the application was customized in the current study to semi-automatically calculate the SWC ratio between two figures for classifying the scalographic pattern of malfunctioning valves, and its efficacy to distinguish valve function was compared to other parameters. Among 155 BLMHVs, 6 valves with consecutive single patterns (type-I) and other 6 with two similar needle-like narrow figures (type-II) were confirmed to be a malfunction by fluoroscopic examination, whereas 14 malfunctioning valves with the tandem pattern which showed a great difference between two figure sizes (type-III) were distinguished from 129 normal valves by the cutoff point of the SWC ratio < 0.482 with the highest AUC (0.960) compared to other parameters by the ROC analysis.

[Surgical Treatment of Acute Infective Endocarditis after Transcatheter Aortic Valve Replacement].

Infective endocarditis (IE) after transcatheter aortic valve replacement (TAVR) is a rare complication, but has a high mortality. An 86-year-old female with symptomatic severe aortic stenosis underwent TAVR at our hospital and she was discharged without complication after 10 days. She was readmitted with high fever and acute heart failure 1 month later. Blood culture revealed Staphylococcus, and echocardiography showed vegetation on the septal cusp of the tricuspid valve and perforation at the membranous ventricular septum. We decided to perform emergency operation due to active infection and intracardiac complication despite appropriate antibiotic treatment. The infected valve was replaced with a bioprosthetic valve and the right ventricular (RV)-left ventricular (LV) communication was closed with a bovine pericardial patch. The patient received the antibiotics for 6 week and was transferred to the previous facility.

The significance of the analysis on scalographic pattern for detecting malfunctioning bileaflet valve with the wavelet analysis.

The authors developed the wavelet analysis system which can detect the splitting of bileaflet mechanical heart valve (BLV) into two spikes on the scalogram, and reported that either consecutive single spike or the split behavior can detect malfunctioning BLV (MBV). The latest study on 12 BLVs suggested that the comparison between two spike areas showed higher potential to detect MBV than the split behavior. The aim of the current study is to review 226 files of BLV sound and to select the suitable scalographic property to differentiate the function of BLV with the split. Eight of 30 MBV files showed consecutive single spike, and the rest of 22 MBV files showed two spikes. Two spike areas can be compared by the following three ratios; the anterior spike area/posterior spike area (Aa/La), its reverse ratio (Pa/Aa) and the smaller spike area/the larger spike ratio (Sa/La). Therefore, the current study compared those three ratios to pursue the suitable ratio to compare two spike areas and its sensitivity to differentiate valve function by the ROC analysis. As a result, the Sa/La was suitable for comparing two spike areas, and only this ratio showed high accuracy to differentiate the function of BVL with the split, and its cutoff value was <0.665. Conclusively, the key for detecting MBV was either consecutive single spike or the mean of Sa/La < 0.665. However, this cutoff point is still tentative due to small number of malfunctioning valves, and other key might be available in future.

Comparison of two spike areas in bileaflet mechanical valve closing sound.

We previously reported our development of a wavelet analysis system which demonstrates that in vivo bileaflet mechanical valve sound splits into two spikes at higher frequency levels and, based on this system, proposed criteria for detecting malfunctioning bileaflet valves (MBVs). However, the results of that study were only tentative due to the small number of patients with MBVs enrolled in the study. Here, we discuss the possibility of new criteria based on the scalographic properties of two spikes of bileaflet valve sound. The study cohort comprised 12 patients who each received a Carbomedics valve. Based on cinefluoroscopy findings, seven valves were classified into a "normal" group, and the other five were classified into a "malfunction" group. Five consecutive valve sounds for each valve were collected for the wavelet analysis in order to re-evaluate the previously proposed criteria and to measure both anterior spike area (Aa) and posterior spike area (Pa) for calculating the spike area ratio (Aa/Pa). The proposed criteria, namely, a single spike or coefficient of variation of <0.1120 detected only two of the five malfunctioning valves, as well as one normal valve to be malfunctioning. The mean Aa/Pa of all malfunctioning valves [2.45 ± 0.63; 95 % confidence interval (CI) ±1.01, 95 % confidence limits (CL) 1.44-3.46] was significantly higher than that of all normal valves (1.17 ± 0.27; 95 % CI ±0.25, 95 % CL 0.92-1.42). Based on this result, we determined the cutoff value of Aa/Pa to be 1.4. The combination of a single spike on the scalogram and an Aa/Pa of >1.4 detected more MBVs than previously proposed criteria. This combination may represent new criteria for detecting MBVs.

New automated wavelet analytical system with a cellular phone for recording intercellular phone remote transmitted bileaflet valve sound.

The wavelet analytical system developed in our institute can detect a malfunctioning bileaflet valve by analyzing the split interval (SI) of bileaflet valve sound (BLVS) caused by asynchronous closure of both leaflets. However, this system is limited in its clinical application because of the complications of both valve sound recording and analytical protocols. This study established a new system that improved upon these limitations, and evaluated its clinical efficiency and the possibility of intercellular phone remote transmission of BLVS (ICTB). Fifty-one valves in 36 patients with St. Jude Medical bileaflet valve replacement were examined by fluoroscopy, 90 BLVS files (42 mitral and 48 aortic valve files) were recorded, and 1720 individual BLVS recordings in these files were analyzed with the new system. The new system consists of a cellular phone for BLVS recording and an automated algorithm for analysis with the Morlet continuous wavelet transform. ICTB was also investigated clinically. The new system showed great improvement over the original system by simplifying BLVS recording and reducing analysis time by approximately 65%. This system detected two malfunctioning valves with coefficients of variation (CV) for SI below 0.112, a previously proposed criterion for malfunction. ICTB also proved to be a useful BLVS recording method for determining SI. The new system described in this study could eliminate the factors limiting clinical application of the old system, and ICTB was found to be a clinically applicable BLVS recording method.

Initial clinical experience with the Heartstring.

OBJECTIVE: The Heartstring is one of the devices that enable proximal anastomosis without clamping the aorta. We have applied the device not only to low-risk patients with normal aortas but also to high-risk patients with diseased aortas. The purpose of this study was to investigate the initial outcomes of using this device. METHODS: The Heartstring was used on 87 patients between January and December 2004. The patients comprised 62 men and 25 women 48-86 years old (mean 68.4 +/- 8.4 years). The ascending aorta was evaluated by computed tomography (CT) scanning before surgery. If a patient's aorta was severely calcified, epiaortic echocardiography was performed. The aortas were ranked into four grades, and the preoperative patient's status were evaluated by the EuroSCORE. Angiography was performed on the third postoperative day. RESULTS: CT scanning revealed that 74 patients had no calcification in the ascending aorta, 10 patients had scattered calcification, and 3 patients had plate-like calcification. The EuroSCORE was 6.86 +/- 1.03. We performed 93 proximal anastomoses and 149 distal anastomoses. The average distal anastomosis was 1.6 +/- 0.6 sites per graft. Of the distal anastomoses, 74.2% were to the circumflex artery territory. Postoperative coronary angiography revealed that all grafts were patent. CONCLUSION: The Heartstring facilitates safe proximal anastomosis, even in high-risk patients. Their short-term outcome was good. The device assists in bypassing circumflex artery territory. Long-term follow-up is necessary.

Re-reconstruction of visceral arteries with thoracoabdominal aortic replacement using a branched graft.

A 44-year-old man, unaffected by Marfan's syndrome, had previously undergone thoracoabdominal replacement for a chronic, type B dissecting aneurysm. Reconstruction of the visceral arteries was performed using an island technique. However, approximately 3 years after the operation, the reconstructed part of the aorta containing the visceral arteries became dilated and an aneurysm formed. We have succeeded both in repairing the aneurysms and "re-reconstructing" the visceral arteries using a branched graft. We conclude that the technique of separate revascularization is worth considering from the beginning, even if the patient does not present with Marfan's syndrome.

Surgical treatment of cardiac myxosarcoma.

A 36-year-old man suffering from exertional dyspnea was admitted to our hospital. An echocardiogram showed a left atrial tumor, which was excised via the left atrial approach. Histological examination of the surgical specimen revealed that it was a myxosarcoma. Twelve months after the surgery, the tumor recurred in the left atrium, and metastatic tumors were found in the right atrium and right ventricle. Surgery was performed once again, but examinations 5 months after the second surgery showed local recurrences and multiple metastases. Although the patient had received chemotherapy, he died 30 months after the first operation.

Wavelet analysis of valve closing sound detects malfunction of bileaflet mechanical valve.

Several studies have reported the asynchronous closure of normal bileaflet valves (NBVs), resulting in a split in its closing sound; however, the clinical significance of this split has never been studied in malfunctioning bileaflet valves (MBVs). The study comprised 218 valves in 184 patients, including normal monoleaflet valves (n = 10), NBVs (n = 198), and MBVs (n = 10). Valve function was confirmed by cinefluoroscopy prior to analysis of the valve sound by the Morlet continuous wavelet transform (CWT). The split interval (SI) for each heartbeat was measured, and the coefficient of variation (CV) of its mean (valve SI) was calculated as a parameter for the fluctuation of the SI. The CWT of monoleaflet valves showed a single spike, whereas NBVs exhibited a clear split. There was no significant difference in valve SI between the aortic and mitral positions; however, the mean of the CV was significantly greater in the mitral position (n = 90, 0.507 +/- 0.254) than in aortic position (n = 108, 0.353 +/- 0.228, P = 0.000045). The split was not found in six (aortic; three, mitral; three) of ten patients with MBVs. The other four patients had a distinct split, but the CV was significantly lower for MBVs (0.138 +/- 0.105) than for NBVs (0.343 +/- 0.221, P = 0.042). Receiver-operating characteristics analysis demonstrated the cutoff line of the CV to be 0.112 for detecting malfunctioning aortic valves with the highest accuracy of 86.1%. This new system using the Morlet CWT can detect MBVs. It will be a useful modality for screening the function of bileaflet valves.

Wavelet analysis of bileaflet mechanical valve sounds.

It has been reported that asynchronous leaflet closure in a bileaflet mechanical valve causes a split in the valve closing sound. We have previously reported that the continuous wavelet transform (CWT) with the Morlet wavelet as modified by Ishikawa (the Morlet wavelet) is the most suitable method among the CWTs for detecting a split in the bileaflet mechanical valve sound because this method can detect the highest frequency signal among the CWT methods with higher time resolution. This is the first article which discusses the acoustic properties of five types of bileaflet valves using the Morlet CWT. Similar behavior of the valve sound split intervals with wide fluctuations over consecutive heartbeats was found to be the common finding for all the bileaflet valves. This result suggests that fluctuation of the split interval proves the normal movement of both leaflets without movement disturbance. The mean differences in the split interval between these bileaflet valves were statistically significant, and the wavelet coefficients of the CWT showed characteristic scalographic patterns, such as a teardrop shape or a triangle beneath the split. However, these two findings gave no valuable information for the diagnosis of bileaflet valve malfunction. A split in the valve closing sound with a fluctuating interval was the common finding in these five normally functioning bileaflet valves, and careful observation of the split's behavior may be a key to diagnosis of bileaflet valve malfunction.

Aortic valve myxoma mimicking vegetation: report of a case.

We report a case of cardiac myxoma of the aortic valve. To our knowledge, this represents only the seventh such case ever documented. A 61-year-old woman underwent an echocardiography to screen for hypertensive-diabetic cardiac complications, which showed a mass on her aortic valve. Although she had not experienced a fever, the mass closely resembled a vegetation, resulting in an initial diagnosis of infective endocarditis. We extirpated the mass and repaired the aortic valve with the patient under cardiopulmonary bypass. The postoperative course was uneventful. Histological examination confirmed that the mass was a myxoma.