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.     

Immediate and long-term results of mitral prosthetic replacement using a right thoracotomy beating heart technique.

OBJECTIVE: Repeat median sternotomy is a potentially dangerous technique providing variable but mainly poor access to the mitral valve. Right thoracotomy is an alternative route previously used to access the mitral valve in the early years of cardiac surgery that offers the advantage of a fresh surgical field in the context of redo surgery. We have reviewed our experience with mitral prosthetic replacement undertaken via a right thoracotomy in order to determine the immediate and long-term results obtained with this approach. METHODS: The operation was carried out on a beating heart using normothermic bypass without cross-clamping the aorta. Arterial inflow was achieved via the femoral artery or ascending aorta and venous drainage with bi-caval cannulae. Pre-, intra- and postoperative data were documented from case note review. Long-term follow-up was established from the UK Heart Valve Registry, referring Cardiologist, direct patient contact and the Scottish Registry for births and deaths. Statistical analysis was undertaken using a desktop computer package. RESULTS: One hundred and twenty-five patients (mean age 63 years) underwent mitral prosthetic replacement by this technique. One hundred and eleven patients (86%) were in NYHA grades III or IV preoperatively. Twenty-two patients (16.6%) had also undergone previous CABG. Thirty-five patients (28%) had undergone two or more sternotomies. Mean bypass time was 83.6 min (SD 43.1). Postoperatively, mean duration of ventilation was 44 h; mean ITU stay was 4 days (SD 5.3) and mean inpatient total stay was 12 days. Thirty-six patients (28.8%) required inotropic support postoperatively. Complication rates were low: pleuro-pulmonary, 30 patients (24%), re-operation for bleeding, four patients (3.2%) and CVA, two patients (1.6%). Eight patients (6.4%) died within 30 days. Ten-year survival figures (Kaplan-Meier) were: 47% for all causes of mortality and 82.9% when only valve related causes of death were considered. Most of the patients (97.5%) had not required re-operation at 10 years. CONCLUSION: Mitral prosthetic replacement via a right thoracotomy on beating heart under normothermic bypass offers a safe alternative to redo median sternotomy in this high-risk group. Operative access is facilitated and procedural time reduced. Complication rates are low and perioperative mortality is lower than that generally reported with conventional surgery.     

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.     

Surgery for cardiac valves and aortic root without cardioplegic arrest ("beating heart"): experience with a new method of myocardial perfusion

Simultaneous antegrade/retrograde warm blood perfusion with a beating heart has not been previously reported as a mean of protecting hypertrophied hearts in cardiac valve and aortic root surgeries. Similarly, beating heart mitral valve surgery via the trans-septal approach with the aorta unclamped, is a novel technique. We, herein, report a series of 346 patients with a variety of cardiac pathologies who were operated upon utilizing a new modality of myocardial perfusion. Among this group of patients, there were 55 patients who were diagnosed with endocarditis of one or more valves. These patients were excluded from this series of patients. Mean age was 59 +/- 12, and there were 196 (67.3%) males and 95 (32.7%) females. There were six aortic root procedures, 90 mitral valve replacements (MVR), 46 mitral valve repairs, 20 MVR+ coronary artery bypass grafting (CABG), 28 tricuspid valve repairs, 106 aortic valve replacements (AVR), 17 AVR+CABG, and 8 AVR/MVR. Crude mortality for the group was 20 of 291 (6.8%). Intra-aortic balloon pump utilization at time of weaning from cardiopulmonary bypass was 6/291 (2.06%), and re-operation for bleeding was needed in 12 of 291 (4.1%) patients. Postoperative stroke occurred in 4 of 291 (1.3%) patients. In these patients, the clinical diagnosis of stroke was made prior to surgery. This initial experience with this new method of myocardial perfusion indicates that results are at least comparable, if not superior, to conventional techniques utilizing intermittent cold blood cardioplegia.     

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.     

On-pump beating heart versus hypothermic arrested heart valve replacement surgery

BACKGROUND: Comparison of neurological parameters in patients undergoing prosthetic heart valve replacement with two operating techniques-either cardioplegic arrest of the heart under hypothermic cardiopulmonary bypass (CPB) or the heart beating on normothermic bypass, with or without cross-clamping the aorta, without cardioplegic arrest. methods: Fifty valvular surgery patients were randomly assigned into three groups. Sixteen patients underwent beating heart valve replacement with normothermic bypass without cross-clamping the aorta, 17 patients underwent the same procedure with cross-clamping the aorta and retrograde coronary sinus perfusion, and the remaining 17 patients had conventional surgery with hypothermic bypass and cardioplegic arrest. RESULTS: Two-channel electroencephalography (EEG) was recorded to assess changes in cerebral cortical synaptic activity and 95% spectral edge frequency values were recorded continuously. Bispectral monitoring was used to measure the depth of anesthesia. Blood flow rates in middle cerebral artery (MCA) were measured by transcranial Doppler (TCD). Reduction in spectral edge frequency (>50%) or bispectral index (BIS) (<20) or transcranial Doppler flow velocity (>50%) was detected in four patients in Group 1, five patients in Group 2, and three patients in Group 3. BIS or EEG values never reached zero, which indicates isoelectric silence during surgery. Gross neurological examinations were normal in all patients postoperatively. CONCLUSION: There is no difference regarding neurological monitoring results between on-pump beating heart and hypothermic arrested heart valve replacement surgery. Also no significant difference was encountered among the groups regarding the clinical outcomes.     

Mitral valve replacement and endocavitary patch repair for a giant left ventricular pseudoaneurysm

We present a case of a giant inferior left ventricular (LV) wall pseudoaneurysm. The patient had New York Heart Association class IV heart failure due to severe mitral valve regurgitation and poor LV function. Our operative approach included right thoracotomy, excision of the mitral valve, and patch repair of the pseudoaneurysm neck from inside of the dilated LV cavity followed by mitral valve replacement. Surgery was performed without aortic cross-clamping on a normothermic perfused beating heart. The patient had an uncomplicated cardiac recovery and is doing well 15 months after surgery.     

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.     

More than ten years' follow-up of the Hancock porcine bioprosthesis in Japan.

From February 1975 through October 1981, 256 Hancock porcine bioprostheses (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) (60 aortic, 169 mitral, and 27 pulmonary/tricuspid position) were implanted in 220 patients (104 male and 116 female, aged 9 to 67 years; mean 43.3) at Kyushu University Hospital in Japan. The procedures include 41 aortic valve replacements, 121 mitral valve replacements, 4 pulmonary valve replacements, 6 tricuspid valve replacements, and 48 combined valve replacements (31 aortic plus mitral, 13 mitral plus tricuspid, and 4 aortic plus mitral plus tricuspid). Hospital mortality was 6.4%. Follow-up was 98% during 8 to 14 (mean 10.5) years. Cumulative follow-up was 1836 patient-years and 2078 valve-years. At 10 years the overall actuarial survival rate, including hospital morality, was 70% +/- 3%, and freedom from valve-related mortality with sudden death was 87% +/- 3%. More than half of the current survivors required no anticoagulant therapy. Freedom from thromboembolism or anticoagulant-related hemorrhage (or both) and prosthetic valve endocarditis was common. Freedom from structural valve failure and reoperation declined more than 9 years after replacement of left-sided heart valves but not after replacement of right-sided heart valves. Sixty-seven patients underwent 68 repeat operations, and there were four deaths (5.9%). The rate of freedom from overall valve-related complications at 10 years was 62% +/- 8% for aortic valve replacement, 53% +/- 5% for mitral valve replacement, 80% +/- 13% for pulmonary/tricuspid valve replacement, and 42% +/- 9% for combined valve replacement. There was a significant difference between pulmonary/tricuspid valve replacement and combined valve replacement (p less than 0.05). The Hancock bioprosthesis is suitable for the replacement of valves in the right side of the heart but not for combined valve replacement.     

Eight year experience with the CarboMedics bileaflet valvular prosthesis.

Two hundred and two patients (97 female and 105 male; mean age: 45. 5+/-9 years) received CarboMedics bileaflet valves during a period of eight years. Ninety-one patients received mitral, 72 aortic and 39 aortic+mitral valve prosthesis. Tricuspid plasty and coronary artery bypass surgery were the concomitant operations in 17 and 12 patients, respectively. The mean follow-up period was 24.7 months and the ratio was 91%. Overall operative mortality was 3.96% (8 patients); 2.78% for aortic valve replacement (AVR), 3.29% for mitral valve replacement (MVR) and 7.7% for double valve replacement (DVR). The late mortality rate was 2.89% for AVR, 2.2% for MVR and 8. 3% for DVR. The main cause of mortality was low cardiac output. The overall survival rate was 91.5% in 2 years. The actuarial freedom from thromboembolism in 2 years was 97% for AVR, 95% for MVR and 84% for DVR. No mortality due to heamorrhagic events was observed. CarboMedics prosthetic heart valves may be used satisfactorily with a low incidence of valve-related morbidity and mortality.     

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.     

Valve replacement in the elderly: a long term appraisal

From July 1972 through July 1983, 360 consecutive patients 70 years of age and older (mean age 74.1; range 70-88 years) underwent 362 valve replacement procedures. There were 122 isolated aortic valve replacements (33.7%; Group I); 70 isolated mitral valve replacements (19.3%; Group II); and 170 patients had combined procedures (47.0%; Group III), which included the replacement of at least one valve. Eighteen patients (5.0%) had previous cardiac surgery. Thirty-two patients (8.8%) were operated as emergencies. Three hundred and thirty-two (86.5%) of all valves implanted were porcine heterografts. Pre-operatively, over one-half (53.6%) of the patients were in New York Heart Association Functional Class IV. The overall hospital mortality was 13.8% (50 patients). The aortic valve mortality was 11.5%, the mitral valve mortality was 15.7%, and the combined procedures 14.7%. The follow-up period for hospital survivors (312 patients) extended from 2 weeks to 127.2 months, with a mean of 38.7 months or a total of 1,006 patient-years. The long term survival computed up to six years shows a 65 +/- 3.8% (standard error of the mean) for the entire group. The aortic valve group survival was 71 +/- 5.6%; the mitral valve group 60 +/- 8.2%; and the combined procedures group was 64 +/- 5.3%. Postoperative functional improvement was significant with 71.8% of the survivors in Class I and 19.6% in Class II. Based on these results, advanced age can no longer be considered a deterrant to cardiac surgery. The porcine heterograft appears to be the valve substitute of choice for this age group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ten year clinical experience with the CarboMedics heart valve implants

We reviewed the histories of 144 patients who underwent heart valve replacement with the CarboMedics prosthesis from 1990 to 2000. There were 74 males and 70 females, with a mean age of 52 years, including 69 aortic valve replacements, 48 mitral valve replacements, and 27 double (aortic and mitral) valve replacements. The mean duration of follow-up was 6.5 years. Early mortality was 7.6% (11 patients). Late deaths occurred in 14 patients, including cardiac-related late deaths in 9 and valve-related deaths in 3. The survival rate including early deaths was 84.7 +/- 3.2% at 5 years and 78 +/- 4.1% at 10 years. Preoperative New York Heart Association Class IV (p = 0.0001) was found to be a significant predictor of cardiac-related late death. Freedom rate from complications at 10 years were embolism 84.7 +/- 4.2% (linearized rate 1.8% per patient year), valve thrombosis 92.7 +/- 2.7% (linearized rate 0.8% per patient year), bleeding 95.6 +/- 2.6% (linearized rate 0.4% per patient year), reoperation 85.9 +/- 4% (linearized rate 1.5% per patient year), valve endocarditis 98.7 +/- 1.3% (linearized rate 0.1% per patient year), and nonstructural dysfunction 90 +/- 3.5% (linearized rate 1% per patient year). There was no structural deterioration. The early and long-term results with the CarboMedics heart valve implantation were acceptable, but valve thrombosis remains a concern in the present study. Further investigation for optimal anticoagulation therapy is necessary to reduce the incidence of valve thrombosis as well as embolic and bleeding complications.     

Triple valve repair for young rheumatic patients.

BACKGROUND: Facing young foreign polyvalvular rheumatic patients, for which long-term anticoagulation is not available, we have chosen to attempt triple valve repair procedures in order to avoid prosthetic implantation in this particular population suffering from triple valve disease. METHODS: Twenty-one young rheumatic patients (mean age:11+/-4 years) underwent triple valve repair procedures including cusp extension on the aortic valve aortic between September, 1992 and December, 2000. Valvular pathology characteristics according to Carpentier's classification included mitral insufficiency type III post+II ant (n=10), type III post (n=4), type II ant (n=2), mitral stenosis (n=5), type III aortic insufficiency (n=21), type I (n=13) and type III (n=8) tricuspid insufficiency. RESULTS: Firstly, the mitral valve disease were corrected using Carpentier's techniques of repair: prosthetic ring annuloplasty (n=16), commissurotomy (n=12), chord transposition (n=11) or shortening (n=4), papillary muscle sliding plasty (n=4) and pericardial patch leaflet enlargement (n=6). Secondly, aortic lesions were corrected using glutaraldehyde stabilized autologous pericardium triple cusps extension technique (n=21). Lastly, tricuspid repairs were always performed on beating hearts using commissurotomy (n=8), prosthetic ring (n=12) or other techniques (n=9) of annuloplasty. The operative mortality was 4.7% (one patient died). Echocardiograms before discharge showed grade I mitral insufficiency in seven patients and grade I aortic insufficiency in five patients. There was no late death during a mean follow-up of 51+/-31 months. Two patients underwent valvular redo surgery because of aortic and mitral plasty deterioration due to rheumatic disease progress. After 5 years, 90% of the patients were free from redo valvular surgery. CONCLUSIONS: In rheumatic patients, autologous pericardial patch extension of the aortic valve permitted widespread use of reconstructive surgery even in patients suffering from triple valve disease. Triple valve repair, in this particular challenging setting of patients, has provided satisfactory initial and mid-term results and could be considered as an interesting palliative surgical approach.     

When do cerebral emboli appear during open heart operations? A transcranial Doppler study

The transcranial Doppler technique enabled the detection of cerebral air emboli in 10 of 10 patients during open-heart valve operations despite standard deairing procedures. With this technique, the occurrence of emboli in the right middle cerebral artery was followed continuously in patients undergoing aortic or mitral valve replacement. Membrane oxygenators were used. Scattered emboli were observed during the insertion of the aortic cannula, at the start of cardiopulmonary bypass, and after the declamping of the aorta with the heart beating while empty. During the period of aortic cross-clamping, no emboli were detected. Despite careful deairing procedures, the recordings indicated a large amount of emboli during filling of the empty beating heart in all 10 patients. Thus, this study indicates that cerebral emboli in open heart procedures are most likely to occur during the redistribution of blood from the heart-lung machine to the patient when the heart is beginning to eject actively, despite careful standard deairing procedures. Meticulous deairing before declamping the aorta is strongly advocated. In addition, a short period of filling of the beating heart before final closure of the aortic incision or vent may decrease the incidence of cerebral emboli. A concomitant reduction in cerebral blood flow by hyperventilation or anesthetics or both during filling of the empty beating heart may also be beneficial.     

Twenty-year experience with the St Jude Medical mechanical valve prosthesis

BACKGROUND: We have prospectively followed all adult St Jude Medical mechanical valve recipients at the Medical University of South Carolina since the initial implant in January 1979 and now present our 20-year experience. METHODS: We prospectively followed 837 valve recipients (aortic valve replacement; n = 478; mitral valve replacement; n = 359) from January 1979 to December 2000 at 12-month intervals. RESULTS: Ages ranged from 19 to 84 years. Follow-up averaged (mean +/- standard deviation) 7 +/- 5 years (98% complete). Patients were in New York Heart Association class III or IV in 77% (aortic valve replacement) and 89% (mitral valve replacement) preoperatively. A 19-mm valve was implanted in 15.5% of aortic valve replacement patients. Coronary bypass was required in 31% of aortic valve replacements and 20% of mitral valve replacements. Operative mortality was 17/478 (3.6%) in aortic valve replacement and 19/359 (5.3%) in mitral valve replacement, and multivariable predictors were 19-mm valve size, 3 or more coronary bypass grafts, and New York Heart Association class IV for aortic valve replacement and New York Heart Association class IV and age for mitral valve replacement. Actuarial survivorship at 10 and 20 years was 57% +/- 3% and 26% +/- 5% for aortic valve replacement and 61% +/- 3% and 39% +/- 4% for mitral valve replacement. Multivariable predictors of late death were African-American ethnicity, New York Heart Association class III or IV, coronary bypass, and age for aortic valve replacement and New York Heart Association class III or IV, coronary bypass, and age for mitral valve replacement. For aortic valve replacement, effective orifice area was univariately (P =.002) but not multivariately (P =.378) predictive of late death. Structural valve deterioration was not observed. For aortic valve replacement, actuarial freedom (at 10 and 20 years) from reoperation was 93% +/- 1% and 90% +/- 2%; thromboembolism, 82% +/- 3% and 68% +/- 8%; bleeding events, 77% +/- 3% and 66% +/- 6%; prosthetic valve endocarditis, 94% +/- 1% and 94% +/- 1%; valve-related mortality, 94% +/- 2% and 86% +/- 4%; and valve-related mortality or morbidity, 58% +/- 3% and 32% +/- 8%. For mitral valve replacement, actuarial freedom (at 10 and 20 years) from reoperation was 96% +/- 1% and 90% +/- 3%; thromboembolism, 77% +/- 3% and 59% +/- 7%; bleeding events, 86% +/- 2% and 65% +/- 8%; prosthetic valve endocarditis, 98% +/- 1% and 96% +/- 2%; valve-related mortality, 89% +/- 0.2% and 74% +/- 8%; and valve-related mortality or morbidity, 63% +/- 3% and 29% +/- 7%. CONCLUSIONS: After 2 decades of observation with close follow-up, the St Jude Medical mechanical valve continues to be a reliable prosthesis.     

复杂性感染性心内膜炎的外科治疗

目的评价瓣周脓肿、心肌脓肿以及瓣膜严重毁损等复杂性感染性心内膜炎手术治疗的近、远期疗效.方法回顾性分析1988年12月至2002年6月手术治疗的复杂性心内膜炎患者57例临床资料,均为原发性心内膜炎,其中感染侵犯主动脉瓣25例、二尖瓣16例、二尖瓣和主动脉瓣16例.术中发现瓣叶严重毁损32例、主动脉瓣周脓肿19例、主动脉根部环形脓肿导致左心室-主动脉连接破坏4例、二尖瓣后瓣环脓肿11例、心肌脓肿6例、瓣膜赘生物形成55例.脓肿清除后遗留残腔采用间断褥式缝合6例、自体心包片修补19例、牛心包片修补6例、聚四氟乙烯膨体补片修补4例;施行以带瓣管道作升主动脉根部替换和左、右冠状动脉移植术4例,主动脉瓣替换术21例,二尖瓣替换术16例,主动脉瓣及二尖瓣双瓣替换术16例.结果早期死亡6例(11%),死亡主要原因为低心输出量综合征、人造心脏瓣膜性心内膜炎和多脏器功能衰竭.随访4个月至14年,平均(5.93±0.20)年.晚期死亡5例,晚期主要并发症为人造瓣膜性心内膜炎.术后1年心功能恢复NYHA分组Ⅰ～Ⅱ级占96%(44/46);5年再手术免除率为(84±3)%,5年实际生存率为(61±9)%.结论复杂性心内膜炎局部组织破坏较多,应限期手术或急症手术,清创后残腔的处理是影响手术本身能否成功以及术后近、远期效果的关键.     

Prosthetic replacement of tricuspid valve: bioprosthetic or mechanical

BACKGROUND: Tricuspid valve replacement is one of the most challenging operations in cardiac surgery. Selection of the suitable prosthesis is still debatable. METHODS: In our institution, between January 1980 and December 2000, 129 tricuspid valve replacements were performed in 122 patients (14.7%). Bioprosthetic valves were used in 32 patients, whereas 97 patients had mechanical valve implantation. Twenty-two percent of replacements were done on men. Mean age was 35.27+/-11.56 years. In all patients, initially an annuloplasty technique was tried. Tricuspid valve replacement was performed when annuloplasty was not sufficient. In most of the cases, tricuspid valve interventions were done under cardiopulmonary bypass and on a beating heart. RESULTS: Early mortality was 24.5%. Patients were followed for 2 to 228 months. Seven patients underwent reoperation because of tricuspid valve dysfunction (7.6%). Nine patients died during the follow-up period. Late mortality was 9.7%. Actuarial estimates of survival in 20 years of follow-up for all tricuspid prosthetic valves, mechanical valves, and bioprosthetic valves were 65.1%+/-9.3%, 68.3%+/-10.6%, and 54.8%+/-12.1%, respectively. For the bioprosthetic valve group, freedom from structural valve degeneration was 90%+/-5.5%; for the mechanical valve group, freedom from deterioration, endocarditis, and leakage was 97.8%+/-4.2%, and freedom from thromboembolism was 92.6%+/-6.9%. CONCLUSIONS: We found that there was no statistically significant difference between the two groups in terms of early mortality, re-replacement, and midterm mortality (p > 0.05). Nevertheless, we recommend low profile modern bileaflet mechanical valves for prosthetic replacement of the tricuspid valve, due to their favorable hemodynamic characteristics and durability.     

The radiofrequency modified maze procedure. A less invasive surgical approach to atrial fibrillation during open-heart surgery.

OBJECTIVE: Patients with mitral valve disease and suffering of atrial fibrillation of more than 1 year's duration have a low probability of remaining in sinus rhythm after valve surgery alone. Intraoperative radiofrequency ablation was used as an alternative to simplify the surgical maze procedure. METHODS: Seventy-two patients with mitral valve disease, aged 63+/-11 years ranging from 31 to 80 years, underwent valve surgery and radiofrequency energy applied endocardially, based on the maze III procedure to eliminate the arrhythmia. The right-sided maze was performed on the beating heart and the left-sided maze during aorta cross-clamping. RESULTS: Surgical procedures included mitral valve repair (n=38) or replacement (n=34) and in addition tricuspid valve repair (n=42), closure of an atrial septal defect (n=2) and correction of cor triatriatum (n=1). The left-sided maze needed 14+/-3 min extra ischemic time. There were two in-hospital deaths (2.7%) and three patients (4.2%) died during follow-up of 20+/-15 months. Among 67 surviving patients, 51 patients (76%) were in sinus rhythm, two patients (3%) had an atrial rhythm and eight patients (12%) had persistent atrial fibrillation or atrial flutter. Four patients had a pacemaker implanted, in one patient because of sinus node dysfunction. Doppler echocardiography in 64 patients demonstrated right atrial contractility in 89% and left atrial transport in 91% of patients. CONCLUSIONS: Intraoperative radiofrequency ablation of atrial fibrillation is an effective and less invasive alternative for the original maze procedure to eliminate atrial fibrillation.     

Acute mechanical valve thrombosis of the St. Jude medical prosthesis

From 1986 to 1996, 2585 patients underwent valve replacement with the St. Jude medical prosthesis. Sixty experienced mechanical valve thrombosis. Seventeen of 60 patients (28.3%) had isolated aortic valve replacements, 33 had isolated mitral valve replacements (55%), and 10 had double valve replacements (16.7%) (aortic and mitral valve replacement). All patients who underwent reoperation for mechanical valve thrombosis were functional Class III or IV. Against medical advice, systemic anticoagulation with warfarin sodium had been discontinued or used only intermittently. Thus, anticoagulant activity was not adequate. The diagnosis of thrombosis was made by clinical examination, laboratory findings, and echocardiography and cineradiography. Of the 60 patients, 9 patients died early after surgery or before discharge. Most of the deaths were attributed to low cardiac output. The overall hospital mortality was 15%. The overall 10-year actuarial survival rate was 82.8+/-1.6%. In our study, reoperation for thrombosed mechanical prosthesis was not an independent parameter determining mortality. Age was the only statistically important hospital mortality predictor. Of this group, 90% suffered mechanical valve obstruction within the first 5 years after operation. These results suggest that valve re-replacement appears to be a suitable surgical treatment for thrombosis of mechanical prosthetic valves, especially in the young. In these patients subsequent anticoagulation management is necessary.