Joseph R. Elbeery

Video-assisted minimally invasive mitral valve surgery

OBJECTIVE This study was done to determine the potential benefits of minimally invasive mitral surgery performed with intraoperative video assistance. METHODS From May 1996 until March 1997, a minithoracotomy and video assistance were used in 31 consecutive patients undergoing mitral repair (n = 20) and replacement (n = 11). Their ages ranged from 18 to 77 years (59 +/- 2.6 years; mean +/- standard error of the mean). Ejection fractions were 35% to 62% (55% +/- 1.5%). Operations were done with either antegrade/retrograde (n = 10) or antegrade (n = 19) cold blood cardioplegia and a new transthoracic crossclamp or with ventricular fibrillation (n = 2). Peripheral arterial cannulation (n = 28) and pump-assisted right atrial drainage (n = 26) were used most often. RESULTS No hospital deaths occurred, but the 30-day mortality was 3.2%. Complications included deep venous thrombosis and a phrenic nerve palsy in one patient each. No patient had a stroke or required reoperation for bleeding. Postoperative echocardiography showed excellent valve function in all but one patient. Cardiopulmonary bypass and arrest times averaged 183 +/- 7.2 and 136 +/- 5.5 minutes, respectively. Compared with 100 patients having conventional mitral valve operations, these patients had significantly shorter hospitalization times (8.6 +/- 0.5 vs 5.1 +/- 0.9 days, p = 0.05). Moreover, 81% of the later cohort were discharged between day 3 and 5 (3.6 +/- 0.2 days). Hospital charges (decreases 27%, p = 0.05) and costs (decreases 34%, p < 0.05) were less than in conventional operations. Patient follow-up suggested minimal perioperative pain and rapid recovery. CONCLUSIONS Early results suggest that video-assisted minimally invasive mitral operations can be done safely. These methods may benefit patients through less morbidity, earlier discharge, and lower cost.

Minimally invasive mitral valve repair using transthoracic aortic occlusion

This report describes a minimally invasive mitral valve repair done through a limited (6-cm) thoracic incision. The patient was supported by peripheral extracorporeal perfusion with cardiac arrest established using a new transthoracic aortic cross-clamp and antegrade blood cardioplegia. The patient was discharged on postoperative day 3 with minimal pain. This less invasive approach to mitral valve surgery may offer combined advantages to patients by increasing comfort, expediting recovery, and decreasing surgical costs by using modified traditional methods compared with specialized intraaortic occlusive balloons.

Fifteen-year experience with minimally invasive approach for reoperations involving the mitral valve.

OBJECTIVE Reoperative sternotomy to address mitral valve pathology carries substantial risk, especially with patent bypass grafts or an aortic valve prosthesis. We previously reported our early experience with minimally invasive right thoracotomy and peripheral cannulation as an alternative strategy, and we recently reviewed our cumulative 15-year hospital outcomes with this approach. METHODS Between June 1996 and April 2010, we performed right minithoracotomy for reoperations involving the mitral valve on 167 patients, 85 (51%) of these since 2006. Seventy-one percent had undergone previous coronary artery bypass grafting and 38% a previous valve procedure. Fibrillatory arrest was used in 77% and aortic clamping and root cardioplegia in 23%. Nineteen procedures were performed with robotic assistance. RESULTS Mitral repair frequency increased during each 5-year interval of our experience (1996-2000, 43%; 2001-2005, 53%; 2006-2010, 72%; P = .019), including 80% of native mitral valves without stenosis. Concomitant procedure frequency, most commonly atrial fibrillation ablation, also increased during each 5-year interval (0%, 21%, 48%; P < .0001). Thirty-day mortality was 3.0% (5/167), 0% since 2005. There were no conversions to sternotomy or aortic dissections. Stroke, in 2.4% (4/167), was statistically unrelated to fibrillatory arrest. Increased New York Heart Association functional class (odds ratio, 5.6; 95% confidence interval 1.1-27.8; P = .037) was the only independent predictor of mortality in multivariable analysis. CONCLUSIONS Our updated experience confirmed the effectiveness of minimally invasive right thoracotomy to treat mitral pathology while avoiding reoperative sternotomy risk. We found fibrillatory and cardioplegic arrest methods to be safe myocardial preservation strategies with this approach.

Intraoperative MIDCABG arteriography via the left radial artery: a comparison with doppler ultrasound for assessment of graft patency

BACKGROUND Minimally invasive direct coronary artery bypass grafting involving beating heart left internal mammary artery to left anterior descending coronary artery anastomoses are performed with increasing frequency. Controversy exists regarding the need for intraoperative assessment of graft patency. METHODS We designed a technique to perform arteriography of the left internal mammary artery by using left radial artery access and standard fluoroscopy to evaluate patency in the operating room. The last 50 of 87 minimally invasive direct coronary artery bypass grafting operations were evaluated by intraoperative arteriography and Doppler ultrasound. Angiograms were performed by the surgeon and involved cannulation and direct injection of contrast medium into the origin of the left internal mammary artery via the left radial artery. RESULTS Total procedure time was less than 15 minutes. No injuries to the left internal mammary artery were identified. Anastomotic occlusions were identified in 4 cases (8%), 2 of which involved sequential diagonal and left anterior descending anastomoses. These were corrected at the time of surgery with 2 cases requiring conversion to standard coronary artery bypass grafting. Qualitative assessment of grafts with Doppler ultrasound failed to definitively identify these occlusions. There were no deaths and no perioperative infarctions. CONCLUSION Intraoperative arteriography of the left internal mammary artery can be performed by the surgeon, and a significant number of anastomotic problems may be identified and corrected by using this technique. Therefore, a 100% early graft patency rate may be attainable.

Intraoperative Catheterization of the Left Internal Mammary Artery via the Left Radial Artery

Minimally invasive coronary artery bypass grafting involving anastomosis of the left internal mammary artery to the left anterior descending coronary artery has become popular in the last year. Critics of this technique infer lower graft patency rates and increased cardiac morbidity. Therefore a technique is described that allows intraoperative selective left internal mammary arteriography to be performed by the surgeon to ensure graft patency before leaving the operating room.

Anterior thoracotomy wound complications in minimally invasive direct coronary artery bypass

BACKGROUND The minimally invasive anterior thoracotomy for beating heart coronary bypass offers a modest 10-cm incision and avoids the morbidity of extracorporeal circulation. This study examines minimally invasive direct coronary artery bypass (MIDCAB) wound complications and contributing comorbid factors. METHODS A retrospective, single-institution review of 165 consecutive MIDCAB cases performed between March 1996 and August 1999 examined all wound abnormalities. Two surgeons performed all cases. RESULTS Wound complications occurred in 15 patients (9.1%), including three (1.8%) incisional hernias, four (2.4%) superficial dehiscences, three (1.8%) wound infections, three (1.8%) chronic pain syndromes, and two (1.2%) seromas. Two patients with incisional hernias required operative repair. The remaining wound abnormalities responded to conservative therapy. Two chronic pain syndrome cases resolved spontaneously, but the third required advanced pain management. In contrast to MIDCAB, the sternotomy wound complications proved significantly less prevalent (n = 5259, 1.1% vs 9.1%, p < 0.005). CONCLUSIONS Although MIDCAB offers several advantages over standard approaches, these data suggest that anterior thoracotomy wound complications are not insignificant and may be underestimated by those exploring minimally invasive options.

An Energetic Analysis of Myocardial Performance

Cardiovascular dynamics is one of the oldest lines of medical research, having its origins in the work of William Harvey in the seventeenth century. Yet despite its long history, conceptual understanding of cardiac performance is advancing more rapidly than ever, and many different scientifc approaches are currently yielding exciting new insights. This chapter reviews 15 years of work from our laboratories at Duke University on the quantitative assessment of diastolic and systolic ventricular function. Our approach to the analysis of chamber geometry, ventricular interaction, and diastolic mechanical properties is described, leading to the observation of a fundamentally linear relationship between myocardial energy production (net external work) and end diastolic fiber length. This relationship is further validated and expanded to provide a useful estimate of myocardial inotropism that is applicable to pathophysiologic analysis of myocardial ischemia and hypertrophy. Finally, recent extensions of this technique to human studies have proven useful to the understanding of cardiopulmonary interactions and valvular heart disease. As knowledge of myocardial adaptive mechanisms improves, enhanced diagnostic and therapeutic capabilities could translate into significant advances in patient care.

Effects of cardiac glycosides on myocardial function and energetics in the conscious dog

The physiological effects of intravenous ouabain on left ventricular (LV) systolic function and metabolic-to-mechanical energy transfer were examined in eight conscious dogs. LV pressure and volume were measured using micromanometers and ultrasonic dimension transducers during transient vena caval occlusions under control conditions and after increasing doses of ouabain. Doppler coronary flow and coronary sinus O2 saturations were used to determine arterial-to-coronary sinus O2 content difference and thereby to calculate LV O2 consumption; total mechanical energy was computed as the sum of LV stroke work and the product of end-diastolic volume and LV mean ejection pressure, neglecting LV unstressed cavitary volume. The slope (10(4) erg/ml) of the stroke work vs. end-diastolic volume relationship increased progressively with rising doses of ouabain from 7.0 +/- 1.6 at control to 9.6 +/- 1.7 after ouabain 0.75 mg (P = 0.0002). Regression analysis of LV O2 consumption (mW/cm3) vs. total mechanical energy (mW/cm3) yielded a linear relationship that did not change with 0.75 mg of ouabain (P > 0.4). These data indicate that ouabain possesses a significant positive inotropic effect on the intact left ventricle without a change in energy transfer efficiency or O2 wasting.