On-pump beating-heart mitral valve plasty without aortic cross-clamping

Patients with ischemic cardiomyopathy often have mitral regurgitation, which should be corrected for better long-term survival. Mitral valve surgery is usually performed during cardiopulmonary bypass under the arrested heart condition. The ascending aorta is cross-clamped and the heart is arrested using a cardioplegic solution. However, because ischemic cardiomyopathy patients often have a severely atherosclerotic ascending aorta and low cardiac function, aortic cross-clamping and cardiac arrest increase the risk of postoperative thromboemboli and low cardiac output syndrome. Under the on-pump beating-heart condition, we performed mitral valve plasty concomitant with coronary artery bypass grafting, tricuspid annuloplasty, left ventricular aneurysmectomy, and the maze procedure without aortic cross-clamping for a patient with ischemic dilated cardiomyopathy and bradycardial atrial fibrillation. The patient had no postoperative complications and recovered rapidly. Thus, to prevent serious postoperative complications, on-pump beating-heart mitral valve surgery without aortic cross-clamping may be a suitable surgical option for patients with ischemic cardiomyopathy.     

Beating heart mitral valve replacement in a patient with a previous Bentall operation

Today, mitral valve replacement is performed under cardioplegic arrest with cross-clamping of the ascending aorta. In the case reported here, mitral valve replacement was performed with an on-pump beating heart technique without cross-clamping the aorta because of diffuse adhesion around the tube graft. A 36-year-old man had undergone a Bentall operation (aortic root replacement + coronary reimplantation) via median sternotomy because of type I aortic dissection 4 years previously in our cardiac center. He was admitted to the hospital complaining of palpitation and dyspnea on mild exertion. Transthoracic echocardiography study revealed third-degree mitral insufficiency. Mitral valve replacement was carried out through re-median sternotomy with an on-pump beating heart technique without crossclamping the aorta. On-pump beating heart mitral valve replacement without a cross-clamp offers a safe approach when excessive dissection is required to place a crossclamp on the ascending aorta.     

Mitral valve replacement with the beating heart technique in a patient with previous bypass graft from ascending to descending aorta due to aortic coarctation

BACKGROUND AND AIM: Conventional mitral valve replacement (MVR) is carried out under cardioplegic arrest with cross-clamping of the ascending aorta during cardiopulmonary bypass. In this case, MVR was performed with on-pump beating heart technique without cross-clamping the aorta because of the diffuse adhesion around the ascending aorta, and tube graft presence between ascending and descending aortas. METHODS: A 47-year-old female patient had aorto-aortic bypass graft from ascending aorta to descending aorta with median sternotomy and left thoracotomy in single stage because of aortic coarctation 2 years ago in our cardiac center. She was admitted to the hospital with palpitation and dyspnea on mild exertion. Transthoracic echocardiography revealed 4th degree mitral insufficiency. RESULTS: MVR was carried out through remedian sternotomy with on-pump beating heart technique without cross-clamping the aorta. CONCLUSIONS: MVR with on-pump beating heart technique offers a safe approach when excessive dissection is required to place cross-clamp on the ascending aorta.     

Marfan's syndrome with annulo-aortic ectasia and ruptured mitral chorda--a case report of combined composite valve graft replacement of the aortic root and mitral valve replacement]

We report a case of Marfan's syndrome with acute heart failure caused by a ruptured mitral chorda that was successfully treated by one operation of combined composite valve graft replacement of aortic root and mitral valve replacement (MVR). A 23-year-old man was admitted to our hospital presenting severe dyspnea and chest pain. Echocardiography and cardiac catheterization studies demonstrated marked annulo-aortic ectasia, aortic regurgitation and significant mitral regurgitation due to a ruptured chorda. In operation, it was found that a chorda of the mitral posterior leaflet had been torn, with the leaflet completely prolapsed to the left atrium, and that the aortic root was dilated to 90 mm in diameter. The ascending aorta was extensively resected leaving those areas of aortic tissue involving the coronary ostia. Then the mobilized coronary arteries were reattached to the composite graft. MVR was performed with preservation of the whole anterior and posterior mitral valve apparatus except for that small part with the torn chorda. Histopathological findings of the aortic wall and mitral valve were compatible with those of Marfan's syndrome.     

Optimal exposure of the mitral valve through an extended vertical transeptal approach

The mitral valve was approached through a vertical transeptal incision extended into the roof of the left atrium in 111 patients. Good exposure was invariably provided even in unfavorable situations such as a small left atrium combined with right ventricular hypertrophy or a previously implanted aortic prosthesis. The only hospital death in the entire series was not related to this approach to the mitral valve. Due to breakage of the suture in the roof of the left atrium and to incomplete reconstruction of the atrial septum resulting in a large left-to-right shunt, 2 patients required reinstitution of cardiopulmonary bypass. Both had a smooth postoperative course. Other intra- or postoperative complications related to the incision did not occur. Duration of cardiopulmonary bypass and aortic occlusion was not significantly different from that of patients operated upon through the conventional left atrial approach in the year preceding the experience embraced by this study. Only 3 of 52 patients who were preoperatively in sinus rhythm were discharged in atrial fibrillation. Enhanced atrial vulnerability was demonstrated preoperatively in all 3. These data support a wide application of the extended vertical transeptal approach in mitral valve surgery.     

Exposure of the mitral valve using flexible self-retaining retractors and an atrial hook

We hereby present our technique for using the self-retaining flexible arm retractor and its attachments for mitral valve exposure. The Aortic Valve Assistant, which was developed for aortic valve exposure, is also very useful for exposure of the inferior wall of the left atrium. Our modified atrial hook provides excellent exposure of the anterior mitral annulus. Extensive dissection and the combined use of the flexible arm and attachments allows us comfortable access for mitral valve operations.     

On-pump beating heart mitral valve surgery without cross-clamping the aorta

BACKGROUND AND AIM: Cardiac reperfusion injury is a well-described complication occurring after ischemia or following cardioplegic arrest. Various strategies have been developed to prevent ischemic reperfusion injury. The aim of this study was to assess the efficacy and applicability of the on-pump beating heart mitral valve surgery without cross-clamping the aorta in order to prevent reperfusion injury. METHODS: The prospective study (between April 2005 and December 2006) included 88 consecutive patients who underwent mitral valve surgery. The operations were carried out on a beating heart using normothermic cardiopulmonary bypass without cross-clamping the aorta, therefore perfusing the heart antegradely through the aortic root. Venting the heart from the aorta and the pulmonary vein provided adequate visualization of the operative field. RESULTS: Seventy-eight patients (88.6%) underwent mitral valve replacement and 10 patients (11.3%) underwent mitral valve repair with this technique. Concomitant surgery was required in 29 patients (32.9%). Twenty-five patients (28.4%) had also undergone previous open heart surgery. Mean cardiopulmonary bypass time was 57.4 +/- 18.4 minutes. Mean duration of ventilation was 12.2 +/- 3.5 hours, mean intensive care unit stay was 1.3 +/- 1.6 days, and mean hospital stay was 6.9 +/- 4.5 days. One-year survival was 96.6% for all causes of mortality. CONCLUSIONS: In this study, we showed that on-pump beating heart operations without cross-clamping is an acceptable surgical choice for mitral valve disease. Complication rates are low and perioperative mortality is lower than that generally reported with conventional technique.     

Leakage test during mitral valve repair

Mitral valve repair is the preferred surgical treatment for mitral regurgitation. Cardiac surgeons must increasingly pursue high-quality mitral valve repair, which ensures excellent long-term outcomes. Intraoperative assessment of a competency of the repaired mitral valve before closure of the atrium is an important step in accomplishing successful mitral valve repair. Saline test is the most simple and popular method to evaluate the repaired valve. In addition, an “Ink test” can provide confirmation of the surface of coaptation, which is often insufficient in the assessment of saline test. There are sometimes differences between the findings of the leakage test in an arrested heart and the echocardiographic findings after surgery. Assessment of the mitral valve in an arrested heart may not accurately reflect its function in a contractile heart. Assessment of the valve on the beating heart induced by antegrade or retrograde coronary artery perfusion can provide a more physiological assessment of the repaired valve. Perfusion techniques during beating heart surgery mainly include antegrade coronary artery perfusion without aortic cross-clamping, and retrograde coronary artery perfusion via the coronary sinus with aortic cross-clamping. It is the most important point for the former approach to avoid air embolism with such precaution as CO₂ insufflation, left ventricular venting, and transesophageal echocardiography, and for the latter approach to maintain high perfusion flow rate of coronary sinus and adequate venting. Leakage test during mitral valve repair increasingly takes an important role in successful mitral valve reconstruction.     

Neurocognitive functions after beating heart mitral valve replacement without cross-clamping the aorta

BACKGROUND AND AIM OF THE STUDY: Although neurologic outcome after cardiac surgery is well-established, neurocognitive functions after beating heart mitral valve replacement still needs to be elucidated. The aim of this study was to compare preoperative and postoperative neurocognitive functions in patients who underwent beating heart mitral valve replacement on cardiopulmonary bypass without cross-clamping the aorta. METHODS: The prospective study included 25 consecutive patients who underwent mitral valve replacement. The operations were carried out on a beating heart method using normothermic cardiopulmonary bypass without cross-clamping the aorta. All patients were evaluated preoperatively (E1) and postoperatively (at sixth day [E2] and second month [E3]) for neurocognitive functions. RESULTS: Neurologic deficit was not observed in the postoperative period. Comparison of the neurocognitive test results, between the preoperative and postoperative assessment for both hemispheric cognitive functions, demonstrated that no deterioration occurred. In the three subsets of left hemispheric cognitive function test evaluation, total verbal learning, delayed recall, and recognition, significant improvements were detected at the postoperative second month (E3) compared to the preoperative results (p = 0.005, 0.01, and 0.047, respectively). Immediate recall and retention were significantly improved within the first postoperative week (E2) when compared to the preoperative results (p = 0.05 and 0.05, respectively). CONCLUSIONS: The technique of mitral valve replacement with normothermic cardiopulmonary bypass without cross-clamping of the aorta may be safely used for majority of patients requiring mitral valve replacement without causing deterioration in neurocognitive functions.     

Improved intraoperative evaluation of mitral valve operations utilizing two-dimensional contrast echocardiography

Whenever possible, precise mitral valve repair is preferable to valve replacement. Present methods for intraoperative detection of mitral regurgitation, primarily hemodynamic measurements and direct palpation, may underestimate or not detect the presence and severity of regurgitation. We have investigated two-dimensional contrast echocardiography as a means of improving our intraoperative assessment of mitral valve function both before and after repair or replacement. After exposure of the heart, a baseline two-dimensional echocardiogram (in modified long- and short-axis planes) is performed using a hand-held 5 mHz mechanical transducer. Five milliliters of agitated 5% dextrose in water is injected into the left ventricle through a transseptal needle to generate detectable microbubbles. In the absence of mitral regurgitation, virtually all microbubbles exit through the aorta; in the presence of regurgitation, a mass of microbubbles reflux into the left atrium. After repair of the mitral valve and immediately after bypass, the contrast echocardiogram is repeated and hemodynamic measurements are obtained. Forty-three patients (37 with mitral valve disease and six additional patients without mitral disease) undergoing cardiac operations were evaluated. Experience with intraoperative two-dimensional contrast echocardiography has accurately demonstrated relatively small degrees of mitral regurgitation when conventional techniques failed to do so and has allowed more precise repair of the residual regurgitation. Two commissurotomy and two annuloplasty patients who were thought to have satisfactory repairs underwent immediate second procedures because of significant residual mitral regurgitation demonstrated solely by this echocardiographic microbubble technique. No complications associated with this technique have developed. We conclude that intraoperative two-dimensional contrast echocardiography is a sensitive and safe technique that allows intraoperative detection of even small degrees of mitral regurgitation and provides a basis for precise repair of mitral valve lesions.     

Accessory mitral valve associated with aortic regurgitation in an elderly patient: report of a case

We encountered a 75-year-old man who complained of exertional dyspnea. An echocardiographic examination showed aortic regurgitation and a tumor in the left ventricular outflow tract. Under complete extracorporeal circulation, we surgically made an incision of the ascending aorta with a slight thickening of the aortic valve and an enlarged annulus. After excising the aortic valve, an examination of the subvalvular region revealed mitral valve-like tissue extending from the annular region of the right coronary cusp to the ventricular septum, while the chordae tendinae was attached to the septum. This issue was excised, and the aortic valve was replaced with a 27-mm SJM valve. The postoperative course was uneventful, and the patient was discharged in good condition on postoperative day 30. An accessory mitral valve is extremely rare. Since this indication for surgical treatment is associated with congenital heart disease or a left ventricular outflow tract obstruction, most patients are young. Our patient had no associated cardiac anomalies and no pressure gradient attributable to a left ventricular outflow tract obstruction. This accessory mitral valve was discovered during aortic valve replacement surgery. To our knowledge, our patient is the oldest reported with an accessory mitral valve to have undergone a surgical resection.     

"Right hand" mitral valve model: a simple and free model available at anywhere

We have devised a simple and cost-free mitral valve model using "right hand", which is placed on the median portion of anterior chest and supinated by 30 degrees. The palm is used to resemble the mitral valve:the thenar eminence, its margin wrinkle, and adjacent palm as the anterior leaflet, coaptation line, and the posterior leaflet, respectively. As the thumb and its origin is assumed as the ascending aorta and aortic valve, this model represents the mitral and aortic valves as viewed from the left atrium. This model is anatomically accurate and facilitates comprehending image orientation in transesophageal echocardiographic probe manipulations.     

Combined valve surgery in end-stage renal disease patient with porcelain aorta and mitral annulus calcification

A 66-year-old woman, who had been receiving regular hemodialysis for 11 years, was referred to our hospital because of heart failure due to combined valve disease complicated by porcelain aorta and mitral annulus calcification. We performed ascending aortic replacement under hypothermic arrest, and double valve replacement and tricuspid valve annuloplasty during rewarming. It was noted that the annulus of P3 of mitral valve had been replaced with atherosclerotic plaque containing calcification. We did not perform débridement. We placed non-everted horizontal mattress sutures from the left ventricle to the atrium on the anterior annulus and P1 to P2 annulus, and everted horizontal mattress sutures on the left atrial wall close to the calcified P3 annulus. Then, we successfully replaced the mitral valve with a 23-mm St. Jude Medical valve in a supra-annular position. The patient was discharged from the hospital 44 days after the operation.     

Combined superior-transseptal approach to the left atrium

The combined superior-transseptal approach to the left atrium was used in 22 patients: to perform a mitral valve repair in 14 patients and mitral valve replacement in 8 patients. Mitral valve operation was combined with other cardiac procedures in 18 patients (82%) and was performed as a reoperation in 3 patients (14%). In all cases there was excellent exposure of the complete mitral annulus and subvalvar apparatus. There were no instances of postoperative bleeding, conduction defects, or intraatrial shunting related to the approach. The combined superior-transseptal approach to the left atrium is an excellent approach that can be used in most reoperations and primary procedures for isolated or combined mitral valve operations.     

Extended vertical transatrial septal approach to the mitral valve

Optimal mitral valve operation requires adequate exposure without impairment of atrial physiology, namely sinus node and atrioventricular node function. We used an extended vertical transseptal atrial approach in 34 consecutive patients. The extended vertical transseptal approach combines two semicircular atrial incisions circumscribing the tricuspid and mitral annuli anteriorly and superiorly, allowing exposure of the mitral valve by deflecting the ventricular side using stay sutures. The right atrium is opened anteriorly along the atrioventricular sulcus. The atrial septum is incised vertically through the fossa ovalis. The right atriotomy is extended superiorly in the right coronary fossa between the right atrial appendage and the atrioventricular sulcus to meet the septal incision. The two joint incisions are extended onto the left atrial roof transversely. At this point, the two semicircular incisions are performed and joined, and mitral valve operation is performed. There were 18 women and 16 men. Five patients had ischemic mitral valve regurgitation, 18 had mitral valve prolapse, and 11 had rheumatic heart disease. The mitral valve was replaced in 17 patients and repaired in 17. There were no perioperative complications associated with the atriotomies, ie, no bleeding, no atrioventricular nodal dysfunction, and no sinus node dysfunction. The extended vertical transatrial septal approach provides good mitral valve exposure without inherent complications.     

The dome of the left atrium: an alternative approach for mitral valve repair.

OBJECTIVE: Surgical repair of mitral insufficiency is most commonly performed through a left atriotomy via the inter-atrial groove or trans-atrial (septal) approach. While the dome of the left atrium approach has been described for mitral replacement concerns have been raised about its adequacy for complex repairs. We report our experience with mitral valve repair carried out through the dome of the left atrium, in comparison with more standard approaches. METHODS: One hundred and thirty-one consecutive patients undergoing mitral valve repair for regurgitation were reviewed retrospectively between 1995 and 2001. Three groups were created based on their surgical approach: inter-atrial groove group (n=43), trans-atrial group (n=18), and dome of the left atrium group (between the superior vena cava and the ascending aorta; n=70). RESULTS: The three groups were similar in terms of pre-operative variables except for significantly older patients in the inter-atrial groove group (P<0.001). The etiology of MR was 24% ischemic (P=ns between groups) and 52% of patients had a concomitant procedure, most commonly coronary artery bypass grafting (P=ns). Valve repairs were achieved using Carpentier techniques including: ring annuloplasty (n=130), isolated posterior leaflet resection (n=69), isolated anterior leaflet (n=11), or bi-leaflet repair (n=19). The overall mortality was 4% with a median length of hospitalization of 7 days and these did not differ significantly between groups. However, longer CPB times (P<0.01) and requirement for prolonged mechanical ventilation (P=0.002) were more frequent in the inter-atrial groove group. CONCLUSION: We report a simple, alternative approach for mitral valve repair via the dome of the left atrium that provides similar outcome to other commonly used approaches.     

A new technique for performing mitral valve repair in a small left atrium

A simple approach for exposing a difficult mitral valve within a small left atrium is described herein through the report of case. Mobilization of the superior vena cava with direct venous cannulation and extended dissection of the interatrial groove provide excellent mitral valve exposure, even in patients with a small left atrium.     

Clinical outcomes after separate and composite replacement of the aortic valve and ascending aorta

Objectives

We sought to compare the clinical profile and outcomes of operations for aortic valve disease and ascending aortic aneurysm in patients treated with aortic valve replacement and supracoronary replacement of the ascending aorta or composite replacement of the aortic valve and ascending aorta (Bentall operation).

Methods

From 1990 through 2001, 133 patients had aortic valve replacement and supracoronary replacement of the ascending aorta, and 452 patients had Bentall operations. Aortic valve replacement and supracoronary replacement of the ascending aorta was performed in patients who had aortic valve disease and dilation of the ascending aorta, whereas the Bentall operation was performed in patients with aortic root abnormality and ascending aortic aneurysm. Mean follow-up was 4.6 ± 3.1 years and was 100% complete.

Results

Patients who had aortic valve replacement and supracoronary replacement of the ascending aorta were older (61 ± 13 vs 52 ± 16 years, P < .001) and more likely to have aortic stenosis, coronary artery disease, and mitral valve disease than those who had Bentall operations. The use of mechanical valves was equal in both groups (42% for aortic valve replacement and supracoronary replacement of the ascending aorta and 43% for the Bentall operation). Operative mortality was 5% for patients undergoing aortic valve replacement and supracoronary replacement of the ascending aorta and 4% for patients undergoing the Bentall operation (P = .45). Survival at 10 years was 57% ± 8% for patients undergoing aortic valve replacement and supracoronary replacement of the ascending aorta and 74% ± 4% for patients undergoing the Bentall operation (P = .04), but the type of operation had no effect on survival. Older age, moderate or severe left ventricular dysfunction, active endocarditis, previous cardiac surgery, and coronary artery disease were independent predictors of death. The freedom from reoperation at 10 years was 95% ± 5% for patients undergoing aortic valve replacement and supracoronary replacement of the ascending aorta and 94% ± 3% for patients undergoing the Bentall operation (P = .18). Reoperations were mostly because of tissue valve failure or endocarditis. The risk of valve-related complications was the same in both groups. No patient required reoperation for aortic root aneurysm after having aortic valve replacement and supracoronary replacement of the ascending aorta.

Conclusions

Aortic valve replacement and supracoronary replacement of the ascending aorta and the Bentall operation provide comparable long-term results. The Bentall operation is more appropriate for patients with aortic root abnormality and a dilated ascending aorta, whereas aortic valve replacement and supracoronary replacement of the ascending aorta is a perfectly acceptable operation for patients with aortic valve disease, normal or mildly dilated aortic sinuses, and a dilated ascending aorta.     

Approach to the mitral valve through a right thoracotomy in potentially hazardous reoperation

BACKGROUND: Repeat sternotomy for mitral valve surgery may be hazardous in some patients. A right thoracotomy avoids the densely scarred area beneath the sternum and provides adequate in-line exposure of the mitral valve. METHODS: Between 1994 and 1997, five patients were reoperated for a mitral valve or prosthesis dysfunction through a right thoracotomy. Indications were three second redo-mitral valve surgeries and two first redo, once in a patient with an aortic prosthesis and once in a patient with patent aortocoronary grafts. The operation was performed without clamping the ascending aorta in moderate hypothermic (four patients) or normothermia (one patient). RESULTS: Exposure of the mitral valve for replacement (four patients) or for repair of a paraprosthetic leak (one patient) was optimal in all patients. Resumption of cardiac function occurred rapidly after repair without specific support. Postoperative course was uncomplicated. Blood loss ranged from 300 to 700 mL. Patients were discharged from 7 to 12 days postoperatively. They are in New York Heart Association (NYHA) functional Class I (four patients) and II (one patient), from 3 to 42 months postoperatively. CONCLUSION: Right thoracotomy provides a direct "in the line of vision" access to the mitral valve. Because complete de-airing of the heart is difficult and respiratory function depressed after a right thoracotomy, this approach seems suitable when technical difficulties are expected in sternal reopening.     

Left atrial isolation associated with mitral valve operations.

Surgical isolation of the left atrium was performed for the treatment of chronic atrial fibrillation secondary to valvular disease in 100 patients who underwent mitral valve operations. From May 1989 to September 1991, 62 patients underwent mitral valve operations (group I); 19, mitral valve operations and DeVega tricuspid annuloplasty (group II); 15, mitral and aortic operations (group III); and 4, mitral and aortic operations and DeVega tricuspid annuloplasty (group IV). Left atrial isolation was performed, prolonging the usual left paraseptal atriotomy toward the left fibrous trigone anteriorly and the posteromedial commissure posteriorly. The incision was conducted a few millimeters apart from the mitral valve annulus, and cryolesions were placed at the edges to ensure complete electrophysiological isolation of the left atrium. Operative mortality accounted for 3 patients (3%). In 79 patients (81.4%) sinus rhythm recovered and persisted until discharge from the hospital. No differences were found between the groups (group I, 80.7%; group II, 68.5%; group III, 86.7%; group IV, 75%; p = not significant). Three late deaths (3.1%) were registered. Long-term results show persistence of sinus rhythm in 71% of group I, 61.2% of group II, 85.8% of group III, and 100% of group IV. The unique risk factor for late recurrence of atrial fibrillation was found to be preoperative atrial fibrillation longer than 6 months. Due to the satisfactory success rate in recovering sinus rhythm, we suggest performing left atrial isolation in patients with chronic atrial fibrillation undergoing valvular operations.