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Background: We hypothesized that gene expression profiles of mitral valve (MV) leaflets from patients with Barlow's disease (BD) are distinct from those with fibroelastic deficiency (FED)., Methods: MVs were obtained from patients with BD (7 men, 3 women; 61.4 ± 12.7 years old) or FED (6 men, 5 women; 54.5 ± 6.0 years old) undergoing operations for severe mitral regurgitation (MR). Normal MVs were obtained from 6 donor hearts unmatched for transplant (3 men, 3 women; 58.3 ± 7.5 years old), and gene expression was assessed using cDNA microarrays. Select transcripts were validated by quantitative reverse-transcription polymerase chain reaction, followed by an assessment of protein levels by immunostaining., Results: The global gene expression profile for BD was clearly distinct from normal and FED groups. A total of 4,684 genes were significantly differential (fold-difference >1.5, p < 0.05) among the three groups, 1,363 of which were commonly altered in BD and FED compared with healthy individuals (eg TGFβ2 [transforming growth factor β2] and TGFβ3 were equally upregulated in BD and FED). Most interesting were 329 BD-specific genes, including ADAMTS5 (a disintegrin-like and metalloprotease domain with thrombospondin-type 5), which was uniquely downregulated in BD based on microarrays and quantitative reverse-transcription polymerase chain reaction. Consistent with this finding, the ADAMTS5 substrate versican was increased in BD and conversely lower in FED., Conclusions: MV leaflets in BD and FED exhibit distinct gene expression patterns, suggesting different pathophysiologic mechanisms are involved in leaflet remodeling. Moreover, downregulation of ADAMTS5 in BD, along with the accumulation of its substrate versican in the valvular extracellular matrix, might contribute to leaflet thickening and enlargement., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Pulmonary embolectomy is often indicated for central pulmonary embolism (PE) with hemodynamic instability, but remains controversial for hemodynamically stable patients with signs of right ventricular dysfunction. Because thrombolytic therapy is often contraindicated postoperatively, we reviewed risk factors and outcomes of pulmonary embolectomy for stable and unstable central PE, particularly in the early postoperative period., Methods: Between October 1999 and September 2013, 115 patients underwent pulmonary embolectomy for central, hemodynamically unstable PE (49 of 115, 43%) or hemodynamically stable PE (56 of 115, 49%). Ten operations for alternate indications (right atrial mass, endocarditis) were excluded for comparison analysis, leaving 105 patients., Results: Mean age was 59 ± 13 years; 46 of 105 patients (44%) had recent surgery (within 5 weeks): orthopedic (12 of 46, 25%), neurosurgery (11 of 46, 24%), or general surgery (10 of 46, 22%). Preoperative demographics did not differ between groups, except for the frequency of cardiopulmonary resuscitation among unstable patients (11 of 49, 22%) versus stable patients (0 of 56, 0%; p < 0.001). Operative mortality for the combined groups was 6.6% (7 of 105): unstable 10.2% (5 of 49) versus stable 3.6% (2 of 56; p = 0.247). Of 11 patients requiring preoperative cardiopulmonary resuscitation, 4 died. Six-month, 1-year, and 3-year survival rates were, respectively, 75%, 68.4%, and 65.8% for unstable PE, and 92.6%, 86.7%, and 80.4% for stable PE (p = 0.018)., Conclusions: This large series of pulmonary embolectomies demonstrates excellent early and late survival rates for patients with stable PE and unstable PE. These findings confirm pulmonary embolectomy as a beneficial therapeutic option for central PE, especially during the postoperative period when thrombolytic therapy is often contraindicated., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The benefits of a minimally invasive approach to off-pump coronary artery bypass remain controversial. The value of completion arteriography in validating this technique has not been investigated., Methods: From April 2007 to October 2009, fifty-six patients underwent isolated minimally invasive coronary artery bypass grafting through a left thoracotomy without cardiopulmonary bypass. Forty-three of these patients underwent completion arteriography., Results: Sixty-five grafts were performed in these 56 patients, (average, 1.2 grafts per patient; range, 1 to 3). Forty-eight grafts were studied in the 43 patients undergoing completion arteriography. There were 4 findings on arteriogram leading to further immediate intervention (8.3%). These included 3 grafts with anastomotic stenoses or spasm requiring stent placement, and 1 patient who had limited dissection in the left internal mammary artery graft and underwent placement of an additional vein graft. These findings were independent of electrocardiographic changes or hemodynamic instability. The remainder of the studies showed no significant abnormalities. There were no deaths. One patient who did not have a completion arteriogram suffered a postoperative myocardial infarction requiring stent placement for anastomotic stenosis. Patients were discharged home an average of 6.8 days postoperatively. There were no instances of renal dysfunction postoperatively attributable to catheterization., Conclusions: Minimally invasive coronary artery bypass is safe and effective. Findings of completion arteriography occasionally reveal previously under-recognized findings that, if corrected in a timely fashion, could potentially impact graft patency and clinical outcomes. Our experience validates this minimally invasive technique., (Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: This study reviews a single institution experience with the Carpentier-Edwards pericardial aortic valve bioprosthesis, concentrating on late outcomes., Methods: From December 1991 to June 2002, 1,000 patients underwent aortic valve replacement with the Carpentier-Edwards pericardial valve (mean follow-up 6.01 +/- 3.56 years). The institutional database was reviewed. Follow-up data were acquired through telephone interviews and mail-in questionnaires. Time-to-event analyses were performed by the Kaplan-Meier method. Mean age was 74.1 years; 545 patients (54.5%) were male. Mean preoperative ejection fraction was 52.5%. Isolated aortic valve replacement occurred in 372 cases (37.2%). Combined aortic valve replacement with coronary artery bypass grafting occurred in 443 cases (44.3%). The remaining 185 patients (18.5%) underwent complex procedures with concomitant mitral, tricuspid, or arch repair. One hundred forty patients (14.0%) had prior aortic valve surgery. Follow-up was 99.4% complete., Results: Overall operative mortality was 7.2% (72 of 1,000). There were 503 late deaths (50.3%). Age-stratified survival at 15 years was 43.7% for patients less than 65 years of age; 18.2% for patients aged 65 to 75; and 9.4% for patients aged more than 75 years. There were 26 failed bioprostheses (2.6%) requiring reoperation. Structural valve deterioration was the cause in 13 of 26 cases (50%), endocarditis in 11 of 26 (42%), and perivalvular leak in 2 of 26 (7.6%). Age-stratified freedom from reoperation due to structural valve deterioration at 15 years was 34.7% for patients less than 65 years of age; 89.4% for patients aged 65 to 75; and 99.5% for patients aged more than 75 years., Conclusions: The Carpentier-Edwards pericardial bioprosthesis shows long-term durability with low rates of structural failure., (Copyright (c) 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Tamponade after cardiac operations often does not manifest the classic clinical or even echocardiographic features of tamponade and may therefore be difficult to diagnose. We present 3 patients with cardiac tamponade in the early postoperative period in whom portable chest roentgenogram revealed marked leftward pulmonary artery catheter displacement at the level of the right atrium and superior vena cava due to adjacent hematoma. Awareness of this radiographic finding may allow immediate triage to a life-saving reoperation, obviating the need for further imaging or diagnostic delay., (2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: We developed a technique for open heart surgery through a small (5 cm) right-anterolateral thoracotomy without aortic cross-clamp., Methods: One hundred and ninety-five consecutive patients (103 male and 92 female), age 69 +/- 8 years, underwent surgery between January 2006 and July 2007. Mean preoperative New York Heart Association function class was 2.2 +/- 0.7. Thirty-five patients (18%) had an ejection fraction 0.35 or less. Cardiopulmonary bypass was instituted through femoral (176 of 195, 90%), axillary (18 of 195, 9%), or direct aortic (1 of 195, 0.5%) cannulation. Under cold fibrillatory arrest (mean temperature 28.2 degrees C) without aortic cross-clamp, mitral valve repair (72 of 195, 37%), mitral valve replacement (117 of 195, 60%), or other (6 of 195, 3%) procedures were performed. Concomitant procedures included maze (45 of 195, 23%), patent foramen ovale closure (42 of 195, 22%) and tricuspid valve repair (16 of 195, 8%), or replacement (4 of 195, 2%)., Results: Thirty-day mortality was 3% (6 of 195). Duration of fibrillatory arrest, cardiopulmonary bypass, and "skin to skin" surgery were 88 +/- 32, 118 +/- 52, and 280 +/- 78 minutes, respectively. Ten patients (5%) underwent reexploration for bleeding and 44% did not receive any blood transfusions. Six patients (3%) sustained a postoperative stroke, eight (4%) developed low cardiac output syndrome, and two (1%) developed renal failure requiring hemodialysis. Mean length of hospital stay was 7 +/- 4.8 days., Conclusions: This simplified technique of minimally invasive open heart surgery is safe and easily reproducible. Fibrillatory arrest without aortic cross-clamping, with coronary perfusion against an intact aortic valve, does not increase the risk of stroke or low cardiac output. It may be particularly useful in higher risk patients in whom sternotomy with aortic clamping is less desirable.

Background: We sought to develop and internally validate a prediction score for all-cause in-hospital mortality in patients who have acute renal failure and require renal replacement therapy after cardiac surgery., Methods: From January 1992 to July 2001, 136 of 14,000 patients (0.9%) had acute renal failure requiring renal replacement therapy after cardiac surgery. Multivariate logistic regression analysis, based on pre-renal replacement therapy variables, was used to construct a predictive score for all causes of in-hospital mortality. Subsequently, the score was validated in 27 patients who underwent surgery between August 2001 and March 2003., Results: In-hospital mortality was 58% (79 of 136). From the logistic regression model, we assigned a score (range, 0 to 6) based on the presence of independent predictors of operative mortality (preoperative creatinine < or = 1.5 mg/dL [odds ratio (OR) = 5.0], hypertension [OR = 4.4], predialysis coma [OR = 9.6], sepsis [OR = 6.4], and total bilirubin > or = 2 mg/dL [OR = 5.6]). Higher scores strongly predicted mortality: patients who scored 3 or higher before the initiation dialysis (n = 54), had a mortality rate of 94% (51 of 54). In contrast, patients who scored 1 or less on this scale (n = 36), had a mortality of 16% (6 of 36). In the validation cohort, the sensitivity of the new score at the cutoff of 2 or fewer points versus 3 or more points was 0.71, the specificity was 0.90, the positive predictive value was 0.92, and the negative predictive value was 0.64., Conclusions: The prediction score represents a simple and accurate tool for predicting in-hospital mortality associated with renal replacement therapy for cardiac surgery patients before the institution of this resource-intensive treatment.

Inflammatory aneurysms of the ascending aorta are exceedingly rare. The principal cause of ascending aortic aneurysms remains arteriosclerosis. We present a patient with an ascending aortic aneurysm caused by active inflammatory disease superimposed on complex atherosclerotic disease of the aorta.

Ventricular septal defect with intramyocardial dissection of the ventricular free wall is a rare complication of myocardial infarction associated with poor prognosis. We describe a patient who developed a ventricular septal defect with intramyocardial dissection of the right ventricular free wall. Initially the patient was successfully stabilized by the placement of a percutaneous closure device. The placement of the device allowed initial hemodynamic recovery of the patient and subsequent definitive surgical repair. This case illustrates the importance of collaboration between interventional cardiologists and cardiac surgeons in the treatment of complex postinfarction ventricular septal defects.

Background: We examined the impact of concomitant coronary artery bypass grafting (CABG) on hospital survival after aortic root replacement. We sought to determine whether CABG procedures that were not originally planned but rather added after the aortic root procedure was completed (CABG/bailout) skewed the results to shift patients with bad outcomes to the CABG group, making the non-CABG group appear undeservedly low risk., Methods: Between May 1992 and January 2001, 369 consecutive patients underwent aortic root replacement. Concomitant CABG was required in 95 patients (26%). Indications for CABG were significant coronary artery disease in 73 patients (20%), active endocarditis or acute aortic dissection involving the coronary orifices in 14 patients (4%), and difficulty weaning from bypass because of regional wall motion abnormality from presumed but unconfirmed coronary artery disease or technical error at coronary ostial reimplantation (CABG/bailout) in 8 patients (2%)., Results: Operative mortality for the entire cohort was 5.7% (21 patients). The operative mortality rate for the non-CABG group was 0.4% (1 of 274 patients), and for the CABG group, 21% (20 of 95 patients; p < 0.001). Independent predictors of operative mortality in the CABG group were New York Heart Association functional class III or IV (odds ratio, 3.9; 95% confidence interval, 1.07 to 14.5), active endocarditis (odds ratio, 9.2; 95% confidence interval, 2.06 to 41.5), acute aortic dissection (odds ratio, 7.6; 95% confidence interval, 1.81 to 32.0), and failure to use retrograde cardioplegia (odds ratio, 6.4; 95% confidence interval, 1.06 to 38.8). The use of CABG/bailout was not a predictor., Conclusions: Adding CABG at the end of an aortic root procedure is a rare event, and because it is rare, there is no significant shift of risk as a result of the CABG/bailout patients on the overall CABG group.

Background: This study evaluates the significance of tricuspid regurgitation (TR) on long-term survival as detected by intraoperative transesophageal echocardiography at the time of orthotopic heart transplantation. Although significant (2+ to 4+) TR after orthotopic heart transplantation is rare, its influence on long-term survival is unknown, warranting further investigation., Methods: Between January 1992 and July 2001, 181 consecutive patients underwent orthotopic heart transplantation. Tricuspid regurgitation was graded by intraoperative transesophageal echocardiography after final separation from cardiopulmonary bypass in 130 of 181 patients (72%)., Results: Although 80% (104/130) of patients had either no (0, n = 77) or trace (1+, n = 27) TR, 9% (12/130 patients) had mild (2+), 10% (13/130 patients) had moderate (3+), and 0.8% (1/130 patients) had severe (4+) TR. The severity correlated strongly with the presence of right ventricular dysfunction (p < 0.001). In a multivariate regression model, gender mismatch (p = 0.002) and right ventricular dysfunction (p < 0.001) were independent predictors for equal to or greater than mild (2+ to 4+) TR (p = 0.015). Although the degree of recipient pulmonary vascular resistance did not influence the grade (p = 0.600), higher pulmonary vascular resistance tended to increase the severity of TR in the setting of prolonged donor ischemic times (p = 0.054). Proportional hazards regression analysis demonstrated significantly decreased survival for patients with mild or greater (2+ to 4+) TR detected by transesophageal echocardiography at the time of transplantation (p < 0.001) and RV dysfunction (p = 0.023)., Conclusions: Even mild (> or = 2+) TR identified by transesophageal echocardiography at the time of orthotopic heart transplant predicts poor late survival, suggesting a possible role for concomitant tricuspid valve repair at the time of transplant. Whether or not tricuspid valve repair will improve long-term survival is unknown.

Percutaneous coronary interventions have progressed from angioplasty and intracoronary stents to the more aggressive rotational atherectomy devices. These technically complex procedures are typically performed on the more diseased anatomy, which causes the likelihood of complications to be more common. In this report, we present our experience with three unusual complications and their surgical management.

This case report illustrates the presentation, diagnosis, and surgical management of an anomalous origin of the right coronary artery from the left coronary sinus in a young adult in whom the right coronary artery was reimplanted directly onto the aorta, rather than bypassed, as is typically done.

Background: With advances in percutaneous coronary interventions, many patients now referred for coronary artery bypass grafting have diffuse coronary artery disease. We undertook this retrospective study to determine whether left anterior descending (LAD) coronary endarterectomy is a safe and effective long-term adjunct to coronary artery bypass grafting in patients who cannot otherwise be completely revascularized., Methods: Between January 1992 and March 2000, 196 of 7,633 (2.5%) consecutive patients underwent LAD coronary endarterectomy with coronary artery bypass grafting. Median age was 67 years (range, 33 to 97 years), 101 patients (52%) had unstable angina, and 182 (93%) were in New York Heart Association class III or IV. Thirty-three patients (17%) had ongoing myocardial infarction; another 17 (9%) had myocardial infarction less than 1 month. Thirty patients (15%) required intraaortic balloon pump preoperatively and 19 (10%) were reoperations., Results: All patients underwent LAD endarterectomy with coronary artery bypass grafting to the LAD. The left internal mammary artery was grafted to the LAD in 151 patients (77%), and 46 of 151 (30%) of these required an additional vein patch to the endarterectomized bed. Concomitant valve procedures were performed in 8 (4%) patients. Overall hospital mortality was 3% (6 of 196). Perioperative myocardial infarction in the LAD territory was 3%. One-year survival was 94% (95% confidence interval, 90% to 97%), whereas 5-year survival was 74% (95% confidence interval, 66% to 80%). Freedom from cardiac events (angina, myocardial infarction, congestive heart failure, percutaneous coronary interventions) was 90% (95% confidence interval, 84% to 94%) at 1 year and 84% (95% confidence interval, 75% to 90%) at 5 years., Conclusions: Despite the presence of diffuse coronary artery disease, coronary artery bypass grafting with LAD endarterectomy offers excellent results with very low hospital mortality and morbidity, and favorable long-term survival.

Right ventricular (RV) failure is a significant source of mortality after cardiac transplantation. The use of RV assist devices (RVAD) as a bridge to recovery has been reported. However, early changes of RV structure and anatomy after RVAD implantation have yet to be described. We report a case of RV failure after transplantation requiring RVAD implantation. After 3 weeks of gradual weaning of inotropic and RVAD support, the device was explanted successfully. Transesophageal echocardiography documents RV hypertrophy and remodeling between RVAD implantation and removal, suggesting a rapid adaptive response of the right ventricle in the presence of pulmonary hypertension.

Background: The purpose of this retrospective study was to evaluate the current incidence, survival, and predictors of mortality for open chest management at our center., Methods: Our database was analyzed to identify adult postcardiotomy patients who left the operating room without primary sternal closure. Medical records were reviewed to determine mortality, postoperative complications, and pertinent hemodynamic data., Results: From November 1997 to June 2000, 5,177 adults underwent cardiac procedures at our center. The incidence of open chest management was 1.7% (87 of 5,177), including 0.7% (16 of 2,254) for isolated coronary artery bypass grafting, 1.6% (15 of 912) for isolated valve, and 5.6% (47 of 839) for combined valve/coronary bypass. Hospital survival was 76% (66 of 87). Major complications included deep sternal infection (n = 4), stroke (n = 8), and dialysis (n = 13). Predictors of mortality by univariate analysis included ventricular assist device insertion (p = 0.003), new onset hemodialysis (p < 0.0005), reoperation for bleeding (p = 0.002), sternal infection (p = 0.042), mean length of delay before sternal closure (survivors = 3.2 days, nonsurvivors = 6.2 days; p = 0.031), higher mean dose of epinephrine at the time of chest closure (2.5 microg versus 0.9 microg, p = 0.011), and longer duration of high dose inotropic therapy (110 hours versus 43 hours, p = 0.002). Multivariate analysis showed ventricular assistance and reoperation for bleeding as independent predictors of in-hospital death with odds ratios of 3.8 and 3.4, respectively., Conclusions: Liberal use of open chest management is useful in patients with postcardiotomy shock, and can be carried out with a relatively low incidence of sternal complications. Patients who require ventricular assistance or exploration for ongoing mediastinal bleeding continue to have a high mortality rate.

Background: Aortic valve surgery after coronary artery bypass grafting (CABG) in the setting of patent pedicled internal mammary artery (IMA) grafts poses a high risk because of the underlying ischemic and valve disease. Unlike mitral valve surgery or CABG, in which aortic clamping (AoX) may be optional, aortic valve surgery uniformly requires AoX unless circulatory arrest is used. Management of the IMA graft in these circumstances has traditionally involved dissection and clamping to prevent regional myocardial warming and cardioplegia "washout" during AoX. An alternative strategy involves avoiding dissection of the IMA, leaving the IMA graft open and establishing moderate-to-deep hypothermia during AoX and cardioplegic arrest. To date, no study has been published documenting the safety and efficacy of the latter practice., Methods: A total of 94 patients who had patent IMA graft and underwent aortic valve surgery under AoX and cardioplegia between April 1992 and March 2001 were analyzed. The IMA was avoided and left open during AoX, and the patients were cooled systemically (median 20 degrees C). Patients ranged in age from 55 to 90 years (median 73.5 years). Ejection fraction was 15% to 83% (median 50%). Of the patients, 18 (19%) underwent minimally invasive upper hemi-resternotomy. Analysis for predictors of outcome was performed., Results: The operative mortality, perioperative myocardial infarction (MI), and stroke rates were 6.4%, 7%, and 11%, respectively. No significant independent predictors of operative mortality or MI could be identified in the multivariate analysis, although a trend was shown for operative mortality with urgent procedures and patients requiring concomitant surgery of the ascending or arch aorta or aortic root. Advanced age and prolonged cardiopulmonary bypass predicted stroke in the multivariate analysis. There were five (5%) IMA injuries, all occurring during reentry or mediastinal dissection, but none in the subgroup of patients who underwent minimally invasive procedures. All patients survived., Conclusions: Patients undergoing aortic valve surgery after CABG in the presence of patent IMA represent a potentially high-risk group. Because AoX is almost uniformly required, a decision regarding the management of the IMA pedicle is needed. We have found that leaving the IMA undissected and unclamped is a reasonable strategy, provided that systemic cooling for myocardial protection is established to prevent regional warming and to compensate for cardioplegia washout effect during AoX.

Performing a precise inferior vena caval (IVC) anastomosis during bicaval orthotopic heart transplantation can sometimes be challenging because of crowding of the operative field by the venous cannula and tourniquet. We performed bicaval orthotopic heart transplantation in 10 patients using an open IVC anastomotic technique with vacuum-assisted venous drainage. A long venous cannula was passed into the IVC through the femoral vein. The IVC anastomosis was performed after removing the IVC tourniquet under vacuum-assisted venous drainage. A precise edge-to-edge IVC anastomosis was successfully performed in all patients. This technique may result in greater anastomotic precision and improved outcomes.

We describe a technique for blood conservation when ABIOMED BVS 5000 blood pumps require exchange because of thrombus formation in the blood pumps. The technique is simple in concept but requires careful planning and coordination between surgeon and perfusionist.

Background: Reoperative coronary artery bypass grafting (CABG) through a left thoracotomy is a challenging operation with no one dominant approach. We developed a tailored strategy for this difficult group of patients, integrating the currently available newer technologies for each patient indication., Methods: Between October 1991 and October 1999, 50 consecutive patients underwent reoperative CABG through a left thoracotomy. Age was 65 +/- 9 years, 40 (80%) were men, and preoperative ejection fraction was 40 +/- 13. In 36 patients (72%) the left internal mammary artery had been placed to the left anterior descending coronary artery during the primary CABG and in 25 of 36 patients (70%) this left internal mammary artery-left anterior descending coronary artery graft was patent. The mean duration from previous CABG was 8.0 +/- 4.8 years. Three approaches were used: (1) conventional cardiopulmonary bypass using fibrillatory or circulatory arrest (n = 33, 66%); (2) Heartport endoaortic balloon occlusion (n = 4, 8%); and (3) off-pump beating heart techniques (n = 13, 26%)., Results: The off-pump CABG technique was used in the majority of recent patients and 1 (7.7%) had to be converted to cardiopulmonary bypass due to hemodynamic instability. When cardiopulmonary bypass was used its duration was 122 +/- 59 minutes and mean temperature on bypass was 24 degrees +/- 6 degrees C. In the 4 patients in whom the Heartport system was used, the median endoaortic occlusion duration was 49 minutes. Patients received an average of 1.4 grafts/patient. In 60 of 70 patients (89%) distal anastomoses were performed to an anterolateral coronary target. There were 3 of 50 (6%) operative deaths, 2 in the conventional group and 1 in the endoaortic balloon occlusion group. The mean length of stay in the 47 survivors was 7.8 +/- 3.9 days (median, 7 days)., Conclusions: Reoperative CABG by left thoracotomy remains a challenging operation. Several techniques, including off-pump CABG, conventional cardiopulmonary bypass, circulatory arrest, and endoaortic balloon occlusion, should be in the surgeon's armamentarium to allow a tailored approach for each operation based on patient indications.

Background: Transmyocardial laser revascularization (TMR) has been established with the carbon dioxide (CO2) laser. The largely unstudied excimer laser creates channels through chemical bond dissociation instead of thermal ablation, thereby avoiding thermal injury. We sought to compare the effects of CO2 and excimer TMR in a porcine model of chronic ischemia., Methods: Pigs underwent ameroid constrictor placement on the circumflex artery to create chronic ischemia. TMR was performed with CO2 (n = 8) or excimer (n = 8) laser 6 weeks later; controls (n = 7) had ameroid placement only. Regional myocardial blood flow (RMBF), determined by radioactive microspheres, and regional myocardial function, determined by percent segmental shortening (%SS), were assessed 18 weeks after ameroid placement., Results: Values are mean +/- SD. In the ischemic zone, RMBF (mL/min/g) was improved in the CO2 (0.73 +/- 0.19) and excimer (0.78 +/- 0.22) groups when compared with controls (0.55% +/- 0.12%, p < 0.05). %SS was also improved in the CO2 (15.2% +/- 5.5%) and excimer (15.3% +/- 5.1%) groups when compared with controls (8.0% +/- 4.2%, p < 0.05)., Conclusions: Excimer and CO2 TMR significantly improve RMBF and regional function in this porcine model of chronic myocardial ischemia despite fundamentally different tissue interactions.

Background: We developed a prosthetic left ventricle (LV) to coronary sinus (CS) shunt (LVCSS) that is autoregulating and provides LV-powered retrograde perfusion of the coronary sinus., Methods: Each of 20 Yorkshire pigs underwent 1 hour of left anterior descending diagonal artery occlusion followed by 3 hours of reperfusion. The controls (n = 5) did not have shunt treatment. The LVCSS group (n = 9) underwent shunt treatment during the ischemic period. The LVCSS with partial coronary sinus occlusion (PCSO) group (LVCSS+PCSO, n = 6) underwent shunt treatment and PCSO during the ischemic period. Vital staining and planimetry techniques were used to determine the area at risk for infarction and the area of necrosis., Results: The area at risk was not significantly different among groups. The area of necrosis was decreased by 53% in the LVCSS group and by 73% in the LVCSS+PCSO group when compared to controls (p<0.01 among all groups)., Conclusions: The LVCSS reduces infarct size in pigs after acute coronary artery occlusion. The addition of PCSO to LVCSS further improves myocardial salvage.

Background: Mitral valve surgery after previous coronary artery bypass grafting presents a challenging problem for the cardiac surgeon. An injury to patent coronary artery bypass grafts, especially internal mammary artery grafts, during reoperation via a redo sternotomy, may be fatal. Therefore, a reliable alternative to the redo sternotomy is desirable to minimize potential injury to internal mammary artery grafts., Methods: Between February 1987 and October 1998, we performed 59 consecutive mitral valve operations after previous coronary artery bypass grafting surgery (CABG). A total of 24 patients (41%) had functioning internal mammary artery (IMA) grafts and represent the population for this study. No patients were excluded for any reason. Of the 24 patients, 20 (83%) were men. Mean age was 66+/-13 years (range 41 to 83 years) and the mean duration from CABG was 5.3+/-3.6 years (range 0.1 to 12 years). Four (17%) had functioning bilateral internal mammary artery grafts. All had 3 to 4+ mitral regurgitation (MR) at the time of mitral valve surgery and the mean preoperative ejection fraction (EF) was 40%+/-14% (range 20% to 74 %)., Results: Twenty-one (88%) patients underwent mitral valve surgery through an anterolateral right thoracotomy and 3 (12%) through a redo sternotomy. Twenty-two (92%) patients, including the 3 patients in whom a redo sternotomy was used, had cannulation of the femoral artery and vein. Two patients required axillary artery cannulation. All 21 patients in whom the mitral valve was approached through a right thoracotomy underwent deep hypothermia (19.6 degrees+/-2.1 degrees C, range 14 degrees to 25 degrees C) without aortic clamping, with a mean duration of CPB of 138+/-46 minutes (range 65 to 249 minutes). In 18 (75%), the MR was ischemic in origin and in 6 (25%) there was myxomatous degeneration. Nine (34%) required valve replacement and 15 (66%) underwent repair. There were no operative or hospital deaths and all patients were discharged to home or to a rehabilitation facility. There were 4 (17%) major complications. Two patients suffered respiratory failure requiring tracheotomy, 1 patient developed a perioperative MI requiring an intraaortic balloon pump and 1 developed heart block requiring a permanent pacemaker. There were no neurologic, peripheral vascular, bleeding, or wound complications., Conclusions: Reoperative mitral valve surgery in the setting of functioning IMA grafts, even in the face of depressed LV function, can be done safely and with minimal morbidity.

Background: Aortic valve replacement or repair becomes a high-risk procedure in patients in whom the ascending aorta cannot be clamped either because of extensive calcification and risk of cerebral embolus or because of extensive adhesions precluding safe dissection and clamping., Methods: We report the results of aortic valve replacement or repair with deep hypothermic circulatory arrest in 3 patients. Techniques to improve results include routine use of epiaortic and transesophageal echocardiography, avoidance of manipulation of the ascending aorta until the circulation is arrested, avoidance of antegrade cardioplegia, routine use of retrograde cardioplegia and retrograde cerebral perfusion, when feasible, and minimal aortotomy (just enough to excise and replace or repair the valve)., Results: Operations were accomplished in approximately 1 hour each with minimal manipulation of the aorta, thus minimizing aortic trauma and subsequent risk of cerebral embolus. Each patient had an unremarkable recovery without neurologic complications., Conclusions: Aortic valve replacement or repair using the "no-touch" technique and deep hypothermic circulatory arrest is the preferred method when dealing with the porcelain or unclampable aorta.

Background: The operative mortality associated with surgical thromboendarterectomy of the pulmonary arteries has decreased at the University of California in San Diego with the application of new techniques. For universal performance of the procedure, however, those factors that contribute to the high operative mortality must be identified. We analyzed our results in 34 consecutive patients undergoing pulmonary thromboendarterectomy to determine those preoperative factors that contribute to operative mortality., Methods: Since 1983, 34 patients with severe, surgically correctable chronic thromboembolic pulmonary hypertension who were judged to be operable by pulmonary arteriography underwent pulmonary thromboendarterectomy. No patient was excluded because of right ventricular failure or hemodynamic severity of disease; the mean pulmonary artery pressure (PAP) was 54 mm Hg, the mean pulmonary vascular resistance (PVR) was 1,094 dynes.s.cm-5, and all patients were in New York Heart Association functional class III or IV., Results: Postoperative course was characterized either by swift recovery (mean length of stay, 13 days) or by rapid demise resulting from pulmonary or right ventricular failure, or both (overall operative mortality, 23%). In survivors, the mean PAP, PVR, cardiac output, and New York Heart Association functional class were significantly improved (p < 0.05). Patients who died had a significantly greater mean preoperative PAP than did those who survived (62.1 +/- 1.2 versus 49.5 +/- 2.3 mm Hg; p < 0.01) and significantly higher PVR (1,512 +/- 116 versus 949 +/- 85 dynes.s.cm-5; p < 0.01). In addition, both a PVR of more than 1,100 dynes.s.cm-5 and a mean PAP of more than 50 mm Hg could accurately predict operative mortality: operative mortality was six times greater in patients with a preoperative PVR of greater than 1,100 dynes.s.cm-5 (41% versus 5.85%) and almost five times greater in those with a mean PAP of greater than 50 mm Hg (37% versus 8%). No intraoperative factors, including the use or duration of circulatory arrest, affected outcome., Conclusions: Patients with severe hemodynamic disease (PVR > 1,100 dynes.s.cm-5 and PAP > 50 mm Hg) have a high likelihood of operative mortality and perhaps should not undergo pulmonary thromboendarterectomy, except at institutions where the operation is performed frequently.