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Notes: Objectives: The purpose of this study was to determine if a device placed externally around the aortic root decreases regurgitant flow in acute aortic regurgitation. Background: Aortic regurgitant flow is dependent on central aortic pressure and the aortic root and leaflet geometry. It may be possible to decrease aortic regurgitant severity by reducing aortic root size or dimension changes. Methods: Aortic regurgitation was created in eight calf heart specimens suspended in a continuous flow system. Retrograde and antegrade aortic flow and distending aortic pressure were measured at baseline and after placement of an external aortic device at the level of the aortic annulus. In two additional specimens, the incompetent aortic valve was visualized fiberoptically before and after placement of the external device. Acute aortic regurgitation was created surgically in four live calves by excising a portion of the aortic leaflets. Antegrade and retrograde flow, left ventricular pressure, and central aortic pressure were measured at baseline, after creation of aortic regurgitation, and after placement of the external device. Results: In the in vitro calf specimens, regurgitant flow decreased from 46.9 cc/sec to 15.1 cc/sec (66.0%± 21.8% decrease) after placement of the external device (p 〈 0.001). The regurgitant orifice area decreased from 0.13 ± 0.04 cm2 to 0.04 ± 0.02 cm2 after device placement (p 〈 0.001). Antegrade flow was reduced to a smaller extent (20.0%± 19.2% decrease) by the device (p 〈 0.05). Placement of the device around the aorta resulted in improved coaptation of the leaflets with a marked reduction in defect size by endoscopic visualization. Use of the external aortic device was associated with improvement in aortic regurgitant severity in three of four calves with surgically created aortic regurgitation. Concluslons: In these preliminary studies, acute experimental aortic regurgitant severity is decreased by the use of an external aortic device, probably due to reduction in aortic annular dimension changes and improved aortic leaflet apposition. Further studies are needed to determine the effectiveness of this device in chronic aortic regurgitation. (J Card Surg 1994;9:304–313)

Notes: A small proportion of patients with significant coronary artery disease referred for coronary artery bypass graft (CABG) surgery have coexistent congenital or valvular disease that, if isolated, would be inadequately severe to justify surgery. While there is general agreement that CABG should be performed for obstruction of major epicardial arteries even without ischemic symptoms in patients having aortic valve replacement (AVR) for aortic stenosis (AS), there has been little or no consideration of whether “mild-to-moderate” AS should be treated by valve repair or AVR at the time of CABG. Between 1975 and 1992, we performed AVR for symptoms or signs of severe AS without significant ischemia on 44 patients with previous CABG. None of thesepatients were considered to have serious AS at the time of CABG surgery 8 to 164 months (68 months) previously. At aortic surgery, ages ranged from 52 to 83 years (73); 38% were female. In 20 patients with available data, transvalvular gradients ranged from 0 to 23 (12) mmHg at CABG and 29 to 95 (62) mmHg at AVR. Aortic valve areas at CABG ranged from 0.9 to 2.2 (1.5) cm2 and at AVR ranged from 0.3 to 1.7 (0.7) cm2. Appearance of symptoms and signs of severe AS occurred in 16% by 3 years; 45% by 4 years; and 75% by 5 years after CABG surgery. These data observations suggest that mild, asymptomatic valve deformity may progress to symptomatic, hemodynamically severe AS within a short time after CABG surgery, well before recurrent symptoms of coronary obstructive disease. Serious consideration of AVR should be entertained for patients with any degree of aortic valve obstruction who must undergo CABG surgery. (J Card Surg 1994;9[Suppl]:145–147)

Notes: Severe posterior annular calcification poses a particular challenge to mitral valve repair. In a series of 252 mitral valve repairs for myxomatous degeneration performed between 1980 and 1993, 14 patients had a severely calcified posterior mitral valve annulus. Ages ranged from 61 to 81 years. Twelve patients were preoperative NYHA Class III or IV, and five patients required concurrent coronary artery bypass procedures. Operative techniques included complete resection of the calcified posterior annulus, resections of portions of the posterior leaflet with leaflet advancement, and placement of an annuloplasty ring. There were no operative deaths and all patients had a postoperative echocardiographic confirmation of relief from mitral regurgitation. During a mean follow-up time of 36 months (6 months to 8 years), there has been one late valve reoperation and only one late death, from thromboembolism in a patient with atrial fibrillation. These data indicate that even in the presence of severe calcification of the posterior mitral annulus, mitral valve repair for myxomatous degeneration can be performed with a low-operative risk and satisfactory long-term results.

Notes: Abstract  Background:“Prophylactic” aortic valve replacement (AVR) in patients with asymptomatic, mild-to-moderate aortic stenosis (AS) at the time of CABG is controversial. In 1994, we reported our initial experience involving 44 patients and have now updated our series in an attempt to further evaluate outcomes. Methods: Between January 1992 and July 2001, 100 consecutive patients underwent reoperative AVR following previous CABG. Forty patients had their initial surgery at the Brigham & Women's Hospital (BWH) and 60 patients had their coronary surgery elsewhere. None of the 40 BWH patients had a mean valve gradient greater than 25 mmHg at the time of CABG. Results: The mean time interval from CABG to AVR for the entire group was 9.0 years (range: 1.4–21 years). Overall operative mortality (OM) was 7% including 5 deaths (10.2%) among 49 patients requiring additional CABG at the time of AVR and 2 deaths (3.9%) among 51 patients without additional coronary artery intervention. This OM rate was a notable decrease from our earlier report of 18.2% (P = 0.07). Furthermore, operative mortality decreased progressively from 15.4% in 1992–1993 to 0% in 2000–2001 (P = NS). Conclusion: The OM of reoperative AVR following CABG has fallen in recent years. Given the relevance of newer techniques and approaches, it may be reasonable to adopt an expectant management approach in patients with asymptomatic mild-to-moderate AS (i.e., mean systolic gradient less than 25 mmHg) at the time of CABG. (J Card Surg 2003;18:507-511)

Notes: Abstract An increasing number of patients with advanced coronary artery disease and diffusely complex atherosclerotic lesions are referred for coronary artery bypass surgery (CABG). Under these circumstances, complete myocardial revascularization with an adequate distal runoff can only be achieved by extensive manual endarterectomy and a reconstructive procedure prior to conduit placement. Because of the numerous septal and diagonal branches of the left anterior descending artery (LAD), an extended and meticulous endarterectomy is warranted. Placement of the internal mammary artery (IMA) on such a widely opened vessel requires reconstruction with a vein patch and the IMA. A modified technique of extended manual endarterectomy, distal vein patch, and proximal IMA reconstruction and revascularization is described. This technique was used in six patients between October 1990 and December 1992 with 100% early survival. This technique is less time consuming and more importantly allows for a direct artery-to-artery anastomosis with the potential for a better long-term patency.

Notes: The myxomatous degenerated, prolapsed, or floppy mitral valve is the most common etiology of mitral regurgitation in North American populations. We performed mitral valve reconstruction for this diagnosis in 252 patients from 1984 to 1993. There were 165 males and 87 females ranging in age from 23 to 84 years (mean 64 years); 93 (37%) were 〉 70 years. One hundred eighty-six were New York Heart Association Functional Class III or IV and 29% (72) underwent concomitant coronary bypass operation. Operations included posterior leafiet resection, anterior leaflet resection treatment of chordal pathology by shortening or Gore-Tex replacement, and ring annuloplasty. There were five operative deaths for an operative mortality of 2%. The operative risk in patients under 70 years was 1 of 159 (0.6%) and 4 of 93 (4%) In patients older than 70 years. Ninety percent of patients are asymptomatic in a follow-up period extending 10 years, while structural valve degeneration requiring reoperation at 5 years was 85%. From 1990 to 1993 there has been a less than 5% absolute incidence of structural valve degeneration. Mitral valve reconstruction for complicated floppy mitral valve Is feasible and offers excellent early and medium-term results. (J Card Surg 1994; 9[Suppl]:278–281)

Notes: Cardiac and cerebral events during coronary artery bypass graft (CABG) surgery remain a major cause of morbidity and mortality. Efforts made to reduce these events will have a significant impact on CABG results. The objective of this study was to examine our results in 394 patients undergoing primary CABG using the single clamp technique that probably has better myocardial and cerebral protective properties than the conventional technique of partial aortic occlusion. Age range was 35 to 88, mean of 66 years, and 168 (43%) were ≥ 70 years of age; 121 (31%) were females, 118 (30%) were diabetic, 339 (82%) were in New York Heart Association Functional Class III or IV, 77 (20%) had a preoperative intra-aortic balloon pump, 213 (54%) were nonelective, 293 (75%) had three vessel disease, and 55 (14%) had critical left main coronary artery stenosis. Antegrade crystalloid cardioplegia was used in the majority of patients, and the distal and proximal anastomoses were sequentially constructed during a single period of total aortic occlusion. The mean number of grafts was 3.5, and 339 (86%) had ≥ 3 grafts; at least one internal mammary artery was used in 346 (88%), a sequential vein or mammary artery in 181 (46%), and 55 (14%) had at least one coronary endarterectomy. The mean cross-clamp time, bypass time, and time to wean off bypass were 63, 83, and 20 minutes, respectively. The overall operative mortality was 11 of 394 (2.8%), a myocardial infarction/low-cardiac output state occurred in 19 (4.8%), and a stroke in 3 (0.8%). The total number of these events or adverse outcomes related directly to the clamping technique was 33 events in 23 patients (8.4%). The low rate of cardiac and cerebral complications associated with the single clamp technique in spite of an increased ischemia time is consistent with our previous results.

Notes: Abstract The duration of safe circulatory arrest for replacement of the ascending aorta for a type A dissection, without additional cerebral perfusion measures, is not clearly defined. If prolonged periods (〉 60 minutes) are anticipated, retrograde cerebral perfusion or selective ante-grade carotid perfusion may be required. The latter requires separate cannulas with subsequent snaring of the cerebral vessels, which may be time consuming and cumbersome. We propose an alternative method whereby the right axillary artery is cannulated for cardiopulmonary bypass and, when the desired hypothermic temperature is achieved, the flows are turned down to 500 mL/min. The origin of the innominate artery is then occluded establishing selective antegrade right carotid artery perfusion. The distal ascending or aortic arch anastomosis is then performed while the remainder of the body is under selective systemic circulatory arrest. The proximal aortic anastomosis is performed after the graft is clamped proximally and flows return to appropriate perfusion levels. (J Card Surg 7 998;4:236–238)