Quality of mitral valve repair: median sternotomy versus port-access approach.

OBJECTIVES: We sought to compare early and late clinical and echocardiographic outcomes of patients undergoing minimally invasive mitral valve repair by means of the port-access and median sternotomy approaches. METHODS: Between 2000 and 2009, 503 patients had mitral valve repair, of whom 143 underwent surgical intervention for isolated posterior leaflet pathology: 61 through port access and 82 through median sternotomy. The port-access group had better preoperative New York Heart Association functional class (P = .007) and a higher rate of elective cases (97% vs 87%, P = .037). Other preoperative characteristics were similar between the groups, including mitral valve pathology and repair techniques. RESULTS: Operative, bypass, and clamp times were significantly longer in the port-access group. Mean hospital stay was 5.3 +/- 2.5 days in the port-access group versus 5.7 +/- 2.5 days in the median sternotomy group (P = .4). Early postoperative echocardiographic analysis showed that most patients in both groups had none or trivial mitral regurgitation and none of the patients had greater than grade 2 mitral regurgitation. Follow-up extended for up to 100 months (mean, 34 +/- 24 months). New York Heart Association class improved in both groups (P = .394). Freedom from reoperation was 97% and 95% in the port-access and median sternotomy groups, respectively. Late echocardiographic analysis revealed that 82% (49/60) in the port-access group and 91% (73/80) in the median sternotomy group were free from moderate or severe mitral regurgitation (P = .11). CONCLUSIONS: In isolated posterior mitral valve pathology, quality of mitral valve repair with the port-access approach can compare with that with the conventional median sternotomy approach.

Aortic root surgery in Marfan syndrome.

BACKGROUND: As the shortcomings of the Bentall operation and its variants in the Marfan syndrome have become apparent, the recent cusp-sparing techniques (remodeling or reimplantation) bear promise of better mid-term and long-term outcomes. OBJECTIVE: To examine the results of aortic root surgery in patients with Marfan syndrome. METHODS: During the period March 1994 to September 2007, 220 patients underwent aortic valve-sparing surgery; 20 were Marfan patients (group 1) who were compared with another 20 Marfan patients undergoing composite aortic root replacement (group 2). Fourteen patients had aortic dissection and 26 had thoracic aortic aneurysm. There were 31 males and 9 females with a mean age of 37.9 +/- 13.8 years. In group 1, reimplantation was used in 13 patients, remodeling in 4, and aortic valve repair with sinotubular junction replacement in 3. In group 2, a mechanical valve conduit was used. Mean logistic Euroscore was 12.27 +/- 14.6% for the whole group, five of whom were emergent cases RESULTS: Group 2 had more previous cardiac procedures compared to group 1 (9 vs. 2, P = 0.03) and shorter cross-clamp time (122 +/- 27.1 vs. 153.9 +/- 23.7 minutes, P = 0.0004). Overall mortality was 10%. Early mortality was 10% in group 2 and 5% in group 1 (NS). Mean follow-up time was 25 months for group 2 and 53 months for group 1. Three patients were reoperated; all had undergone the remodeling. Five year freedom from reoperation and death was 86% and 90% in group 2 and 70% and 95% in group 1 (P = 0.6, P = 0.6), respectively. CONCLUSIONS: Late survival of patients with Marfan syndrome was similar in both groups. Root reconstruction tends towards a higher incidence of late reoperations if the remodeling technique is used. We now prefer to use the reimplantation technique.

[Minimally invasive video-assisted mitral valve repair or replacement].

BACKGROUND: Following the introduction of endoscopic techniques to other surgical fields such as general surgery, gynecology urology and thoracic surgery, cardiac surgeons sought their own methods of using minimally invasive techniques. OBJECTIVES: To examine our operative and mid-term results of mitral valve surgery using minimally invasive video-assisted mitral valve surgery. METHODS: From January 2000, 130 patients underwent minimally invasive cardiac surgery through small right thoracotomy, 72 patients underwent video-assisted mitral valve repair or replacement (52 repair and 20 replacement). Patients were selected for the procedure according to several inclusion criteria. RESULTS: Intraoperative transesophageal echocardiography revealed excellent functional results. There was one intraoperative conversion to mid-sternotomy. There were no mortalities and only one complication CVA that occurred 24 hours after surgery. CONCLUSIONS: Thoracoscopic assisted mitral valve repair (via port access) has the potential to provide all the advantages of minimally invasive surgery: accelerates recovery, decreases pain, and maintains overall surgical efficacy, while avoiding the complications and pathology of midsternotomy. For appropriate patients, this is the method of choice in our department.

[Aortic valve sparing surgery].

BACKGROUND: Over the past 20 years, a series of procedures have been designed to reconstruct the aortic root of patients with aortic insufficiency, in whom the pathology and hence, the surgery, spares the valve leaflets. The objective of this current study was to evaluate our midterm results comparing the reimplantation technique with the remodeling technique in patients with aortic regurgitation due to aortic dissection, aortic root and ascending aortic aneurysms. PATIENTS AND METHODS: During the years 1993 and 2006 we operated on 209 patients with aortic regurgitation secondary to dilatation of the aortic root or ascending aorta with or without aortic dissection. Mean age was 59 years (range 21-81 years), 69% of the patients were males; 91 patients had chronic aneurysm, while 118 patients presented with acute dissection. Thirty-nine patients had Marfan syndrome or it's form fruste. Post-operative follow-up (FU) was 82% complete (172 patients) with mean follow-up time of 66 months, and completion of FU was continued. RESULTS: Thirty-nine patients underwent the reimplantation technique, 89 patients underwent the remodeling technique. Twenty-five patients underwent only replacement of the ascending aorta on the level of the STJ, 11 patients had replacement of the ascending aorta and one sinus. In 45 of the cases bio-glue was used in addition to replacing the ascending aorta. Overall, 30 days mortality was 5.7% (12 patients out of 209). There was no difference in mortality rates among the groups of patients who underwent reimplantation (chronic aneurysm vs Acute dissection), but significantly higher mortality rate was observed among patients who had aortic dissection and underwent the remodeling technique compared to the same group of patients who underwent reimplantation (6.7% vs 1.1%, P < 0.025). It was also found that Marfan patients who had aortic dissection had significantly higher mortality rate when undergoing the remodeling technique (7.6% Vs 0%, p < 0.01). Recurrence of AI more than 2+ occurred in 11 patients, ten from the remodeling and one from the reimplantation group (P = 0.17). Among Marfan patients, recurrence of AI more than 2+ occurred in two patients, both underwent remodeling and both had dissection of the ascending aorta involving the sinuses of Valsalva. Reoperation due to Severe AI was needed for 8 patients, all from the remodeling group and all were non-Marfans. CONCLUSIONS: In acute dissection reimplantation provides better haemostasis and there may be more stable repair, both in Marfan and non-Marfan patients. In Marfans it seems that the reimplantation technique provides better long-term results.

Improved viability and reduced apoptosis in sub-zero 21-hour preservation of transplanted rat hearts using anti-freeze proteins.

BACKGROUND: Freeze-tolerant fish survive sub-zero temperatures by non-colligatively lowering the freezing temperature of their body fluids using anti-freeze proteins (AFPs). We sought to evaluate and compare the effects of prolonged sub-zero cryopreservation of transplanted rat hearts using AFP I or AFP III. METHODS: Two heterotopic rat heart transplantation protocols were used. In Protocol 1 (n = 104), hearts (n = 8/group) were preserved for 12, 18 and 24 hours in University of Wisconsin solution (UW) at 4 degrees C, UW at -1.3 degrees C, UW/AFP I at -1.3 degrees C and UW/AFP III at -1.3 degrees C, with and without nucleation. Post-operative evaluation consisted of visual viability scoring of the hearts after 60 minutes. Protocol 2 (n = 58) involved evaluation of 24-hour post-transplant viability, echocardiography (fractional shortening [FS], left ventricular end-systolic and -diastolic diameter [ESD, EDD] and anterior and posterior wall systolic and diastolic thickness [AWT-S, AWT-D, PWT-S, PWT-D]), TUNEL staining and electron microscopy (EM) findings for hearts preserved for 18, 21 and 24 hours in UW at 4 degrees C or UW/AFP III at -1.3 degrees C. RESULTS: Hearts preserved in UW at -1.3 degrees C with nucleation froze and died. Three of 8 hearts preserved in UW at 4 degrees C for 24 hours died, whereas all hearts preserved at -1.3 degrees C survived. Hearts preserved in UW/AFP for 18 and 24 hours at -1.3 degrees C had superior viability scores compared with those in UW at 4 degrees C. Hearts in AFP III at -1.3 degrees C displayed greater AWT-S and AWT-D (3.5 +/- 0.2 vs 2.4 +/- 0.2, p < 0.05, and 3.5 +/- 0.2 vs 2.2 +/- 0.2, p < 0.05, respectively) after 18-hour preservation. In the 21-hour preservation group, AFP-treated hearts displayed improved echocardiographic systolic contraction indices, including: improved FS (27 +/- 3.7 vs 15 +/- 4, p = 0.04); diminished ESD (0.28 +/- 0.57 vs 0.47 +/- 0.6, p < 0.05); greater AWT-S (3.4 +/- 0.18 vs 2.8 +/- 0.2, p < 0.05); and fewer positively TUNEL-stained nuclei per specimen (35 +/- 14 vs 5.3 +/- 2.7, p = 0.04). Also, improved EM scores were noted compared with UW at 4 degrees C. CONCLUSIONS: In prolonged sub-zero cryopreservation, AFPs protect the heart from freezing, improve survival and hemodynamics, and reduce apoptotic cell death.

Treatment of deep sternal wound infections post-open heart surgery by application of activated macrophage suspension.

Postoperative sternal wound infection remains a significant complication and generally causes considerable morbidity and mortality. Macrophages play a major role in the process of wound healing. In order to evaluate the efficacy of local injection of activated macrophage suspensions into open infected sternal wound space, a retrospective case-control study was conducted. Sixty-six patients with deep sternal wound infection treated by activated macrophages (group 1) and 64 patients with deep sternal wound infection treated by sternal reconstruction surgery with various regional flaps (group 2), were matched for gender, age, and risk index. In up to 54 months of follow-up of group 1, 60 patients (91%) achieved complete wound closure. Two (3%) late deaths occurred unrelated to the procedure. Mortality rate in group 2 was 29.7% (19/64). Duration of hospitalization was 22.6 days in group 1 vs. 56.2 days in group 2. Patients with deep sternal wound infection following open heart surgery that were treated by activated macrophages had significantly less mortality as well as significant reduction of hospitalization in comparison to the surgically treated group. These results illustrate the advantages of using a biologically based activated macrophage treatment.

Long-term arm morbidity after radial artery harvesting for coronary bypass operation.

BACKGROUND: The use of the radial artery (RA) in coronary bypass operations has become increasingly popular in recent years, but there is almost no documentation regarding the midterm and long-term arm complications. METHODS: Between January 1 and December 31, 1998, 109 patients underwent operations for myocardial revascularization employing a pedicled RA as 1 of the coronary grafts. The patients were surveyed for subjective arm morbidities at 2 times during their follow-up: short term (mean, 7 months postoperatively; range, 0.3-14 months) and long term (mean, 49 months postoperatively; range, 46-57 months). RESULTS: At the short-term follow-up, 33 (33.3%) of the patients had some complaints regarding the arm that was operated on, with 4 (4%) of the patients reporting arm disability with complaints that focused on pain (11, 11%), numbness (15, 15%), and parasthesias (12, 12%). At the longterm follow-up, only 9 patients (10.5%) still experienced some sort of inconvenience with the arm that was operated on, with 1 case of functional disability, 4 complaints (4.6%) of residual parasthesias, and 1 report (2.3%) each of pain or numbness. All but 2 of the patients with complaints at the short-term follow-up reported amelioration of symptoms at the long-term follow-up. CONCLUSION: It appears that severe arm disability early after RA harvesting is likely to dissolve with time. Our favorable late follow-up results support the continuation of the employment of the RA as a conduit for coronary artery bypass grafting operations.

Subzero nonfreezing cryopresevation of rat hearts using antifreeze protein I and antifreeze protein III.

The purpose of the present study was to evaluate whether AFPs protect the heart from freezing and improve survival and viability in subzero cryopreservation. Hearts were subject to 5 preservation protocols; University of Wisconsin solution (UW) at 4 degrees C, UW at -1.3 degrees C without nucleation, UW at -1.3 degrees C with nucleation, UW AFP I (15 mg/cm(3)) at -1.3 degrees C with nucleation, and in UW AFP III (15 mg/cm(3)) at -1.3 degrees C with nucleation. Hearts were preserved for 24, 28, and 32 h, rewarmed and connected to the working isolated perfusion system. Data [heart rate (HR), coronary flow (CF), and developed pressure (dP)] was collected 30 and 60 min after reperfusion. Hearts preserved at -1.3 degrees C without AFPs froze, while hearts preserved with AFP did not freeze when nucleation was initiated and survived. Survival and dP of hearts preserved for 24h at -1.3 degrees C using AFP III was better than those preserved at 4 degrees C, (dP; 1.4 vs. 0.8, p<0.05). Four of six hearts and six of six hearts died when preserved at 4 degrees C for 28 and 32 h, respectively, all of the hearts that were preserved at -1.3 degrees C with or without AFPs survived after 28 h (n=18) and 32 h (n=18). CF was higher in UW -1.3 degrees C group without attempted nucleation than in AFP I and AFP III groups after 28 and 32 h (3.4 vs. 1.7, p<0.05, and 3.4 vs. 1.7, p<0.05, respectively). In conclusion, AFPs were found to protect the heart from freezing and improve survival and dP (AFP III) in prolonged subzero preservation.

Prolonged 24-hour subzero preservation of heterotopically transplanted rat hearts using antifreeze proteins derived from arctic fish.

BACKGROUND: Arctic fish survive subzero temperatures by producing a family of antifreeze proteins (AFPs) that noncolligatively lower the freezing temperature of their body fluids. We report 24-hour storage of mammalian hearts for transplantation at subzero temperatures using AFPs derived from arctic fish. METHODS: Forty-two heterotopic transplantations were performed in isoimmune Sprague-Dawley rats. Harvested hearts were retrogradely infused with cold 4 degrees C University of Wisconsin (UW) solution and were preserved in a specialized cooling bath at two target temperatures, 4 degrees C and -1.3 degrees C for 12,18, and 24 hours (6 experiments/group). Preservation solutions were UW alone for the 4 degrees C group, and UW with 15 mg/mL AFP III for the -1.3 degrees C group. After hypothermic storage the hearts were heterotopically transplanted into isoimmune rats. Viability was assessed and graded on a scale of 0 to 6 (0 = no contractions to 6 = excellent contractions). Transplanted hearts were then fixed in vivo and were subject to electron microscopy and histopathologic examination. RESULTS: None of the hearts preserved at -1.3 degrees C in UW/AFP III solution froze. All control hearts preserved at -1.3 degrees C without AFP protection froze and died at reperfusion. Viability of hearts preserved at -1.3 degrees C in UW/AFP III solution was significantly better after 18 hours of preservation, 30 and 60 minutes after reperfusion (median, 5 versus 3 and 6 versus 3, respectively; p < 0.05) and after 24 hours of preservation 30 and 60 minutes after reperfusion (median, 4.5 versus 1.5 and 5 versus 2, respectively; p < 0.05). Histologic and electron microscopy studies demonstrated better myocyte structure and mitochondrial integrity preservation with UW/AFP III solution. CONCLUSIONS: Antifreeze proteins prevent freezing in subzero cryopreservation of mammalian hearts for transplantation. Subzero preservation prolongs ischemic times and improves posttransplant viability.

Minimally invasive video-assisted mitral and aortic valve surgery--our initial clinical experience.

BACKGROUND: After the introduction of endoscopic techniques to other surgical fields like general surgery, gynecology and thoracic surgery, cardiac surgeons sought their own methods of using minimally invasive techniques. OBJECTIVES: To examine whether this approach is less invasive and yields better results, more desirable cosmetic results, and a more rapid and complete rehabilitation, maintaining safety, efficacy, and outcome equivalent to those of more established procedures, such as median sternotomy. METHODS: From January 2000 to July 2001, 22 patients underwent video-assisted port-access mitral or aortic valve repair or replacement with the Heartport system in our department, and one underwent closure of atrial septal defect. RESULTS: Intraoperative transesophageal echocardiography revealed excellent functional results. Total operating room time, perfusion time, and cross-clamp time with this technique decreased with our growing experience and remains stable. There were no intraoperative reversals to mid-steronomy, no mortalities, and only one complication 24 hours after surgery. CONCLUSIONS: Thoracoscopic assisted cardiac surgery (via port access) provides all the advantages of minimally invasive surgery, accelerates recovery, decreases pain, and maintains overall surgical efficacy, while avoiding the complications and pathology of mid-sternotomy. For appropriate patients, this is the method of choice in our department.

Preservation of myocyte structure and mitochondrial integrity in subzero cryopreservation of mammalian hearts for transplantation using antifreeze proteins--an electron microscopy study.

OBJECTIVE: Freeze tolerant fish and insects in nature are able to survive subzero temperatures by noncolligatively lowering the freezing temperature of their body fluids using a family of thermal hysteresis proteins (antifreeze proteins, AFPs) specific for each species. Past efforts to cryopreserve mammalian hearts using these proteins were unsuccessful. We report the first successful subzero cryopreservation of rat hearts using fish derived antifreeze proteins with preservation of myocyte structure. METHODS: Heterotopic heart transplantations were performed in isoimmunic Sprague Dawley rats. Donors' hearts were arrested using University of Wisconsin (UW) solution and preserved in UW solution containing AFP I (six experiments) or AFP III (six experiments) at concentrations of 15-20 mg/cc for 2-6 h at subzero temperatures ranging from -1.1 to -1.3 degrees C. Four control experiments were performed by preserving harvested hearts in UW solution alone at -1.3 degrees C for 6 h. In all experiments ice was added in the solution for crystallization. Heterotopic transplantations were performed in the abdomen of the recipient rats. Viability was visually assessed and graded on a scale of 1 (poor contraction) to 6 (excellent contraction). The hearts were then fixed in vivo and processed for electron microscopy study. RESULTS: All hearts preserved at subzero temperatures using AFP I or AFP III survived displaying viability scores of 4-6 1 h after transplantation. Three of the four control hearts that were preserved at -1.3 degrees C without the protective effect of AFP froze and died upon reperfusion. Electron microscopy study of hearts preserved with AFP demonstrated preservation of myocyte structure and mitochondrial integrity. CONCLUSION: Subzero cryopreservation of mammalian hearts for transplantation using AFP I or AFP III is feasible with preservation of myocyte structure and mitochondrial integrity.

Multidisciplinary intervention for control of diabetes in patients undergoing coronary artery bypass graft (CABG).

In Israel, as elsewhere, diabetes mellitus is highly prevalent among patients undergoing coronary artery bypass graft (CABG). The bulk of evidence, derived retrospectively, suggests that poor control of diabetes predisposes to complications of CABG and increases mortality; but the findings in a number of studies fail to support that impression. Anticipating a prospective investigation designed to resolve this issue, we have carried out a preliminary study of 147 consecutive patients with diabetes who were hospitalized for elective CABG during 1998. Our objective was to determine how well and how often diabetes could be controlled in accordance with selected metabolic goals in the brief interval between hospital admission and surgery and during the operation itself and in the postoperative period. The task was undertaken by a multidisciplinary team, in cooperation with the Department of Cardiac Surgery. The metabolic goals were: fasting blood glucose consistently between 65-140 mg/dl before and after surgery and 120-180 mg/dl at the time of surgery; and postprandial blood glucose consistently <180 mg/dl. These goals were achieved in 18.1% of fasting blood glucose measurements before and after surgery, 22.1% of preprandial and 14.6% of postprandial blood glucose levels consistently <180 mg/dl. There were no clinical episodes of hypoglycemia. Due to the low incidence of major infection related complications (deep sternal wound infection in only 3 patients (2.0%)) no significant statistical conclusions on the relations between glucose control and these complications could be drawn. The means of all values of FBG and of hemoglobin A1c were significantly higher among patients with complications (n=49) than in those without (P=0.01).