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ABSTRACT: OBJECTIVE: The aim of the study was to determine whether using the in situ internal thoracic artery (ITA) graft ipsilateral to the arteriovenous fistula adversely affects the outcomes after isolated coronary artery bypass grafting (CABG) in the dialysis-dependent patients to answer the concerns of a possible steal and consequent myocardial ischemia. METHODS: We categorized 155 dialysis patients undergoing isolated CABG between January 1993 and December 2011 into 108 patients (70%, ipsilateral group) whose left anterior descending artery (LAD) was revascularized with the ITA ipsilateral to the arteriovenous fistula and 47 patients (contralateral group) whose LAD was grafted with the ITA opposite to the fistula, to compare their early and late outcomes. RESULTS: While 94% of the ipsilateral group had left fistula, 55% of the contralateral group had left fistulas. The LAD was grafted with the left ITA in 94% of the ipsilateral group, whereas it was grafted with left (49%) or right (51%) ITAs in the contralateral group. There was no significant difference in hospital mortality between the groups (ipsilateral 10.2% vs contralateral 10.6%). After follow-up for 55 ± 42 months, the overall survival (ipsilateral 58% vs contralateral 65% at 5 years) and cardiac event-free rates (ipsilateral 74% vs contralateral 68% at 5 years) were also similar between the groups by log-rank tests (P = .90 and P = .07). CONCLUSIONS: Revascularization of the LAD using the in situ ITA graft ipsilateral to the arteriovenous fistula increases neither the operative mortality nor the risks of late death and cardiac events after isolated CABG in dialysis patients.
The Journal of thoracic and cardiovascular surgery 02/2013; · 3.41 Impact Factor
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ABSTRACT: OBJECTIVES: Intracoronary shunts have been developed for a bloodless field and preserved forward flow preventing ischemia during off-pump coronary artery bypass (OPCAB) surgery. However, reports directly measuring the forward flow through the shunt in clinical settings are lacking. METHODS: Using a 7.5-MHz Doppler probe, we investigated the coronary flow through a 1.5-mm shunt inserted into the left anterior descending artery (LAD) for anastomosis with the internal thoracic artery during OPCAB in 30 consecutive patients. The following Doppler flow parameters were obtained before and after shunting: peak velocity, mean velocity, time-velocity integral, and flow. RESULTS: No patients developed significant electrocardiographic changes and the peak value of postoperative myocardial band of creatine kinase was 17 ± 16 IU/L. All Doppler flow parameters of the LAD decreased significantly after shunting; peal velocity: 71.3 ± 34.6 cm/second to 54.5 ± 25.3 cm/second (-24% ± 27%), mean velocity: 33.3 ± 18.3 cm/second to 26.3 ± 14.0 cm/second (-21% ± 23%), and time-velocity integral: 28.7 ± 12.1 cm to 19.0 ± 7.1 cm (-28% ± 14%), and flow: 38.7 ± 16.8 mL/minute to 25.0 ± 9.5 mL/minute (-31% ± 13%) (P < .01). CONCLUSIONS: The LAD flow is preserved at least 50% through a 1.5-mm intracoronary shunt, although the flow pattern was attenuated, during OPCAB anastomosis. The Doppler evaluation of the coronary artery flow before and after shunting is useful to justify the protective use of the shunt on myocardial perfusion during OPCAB.
The Journal of thoracic and cardiovascular surgery 11/2012; · 3.41 Impact Factor
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ABSTRACT: BACKGROUND: Markedly higher hospital and long-term mortality after coronary artery bypass grafting (CABG) have been reported in hemodialysis (HD)-dependent patients. We tried to identify the predictors for short-term and long-term outcomes after CABG, which have not been well studied. METHODS: Between 1993 and 2010, 152 patients undergoing HD (117 men; HD duration of 8.7 ± 8.0 years) underwent isolated CABG. Our strategies included use of a single internal thoracic artery (ITA) in patients with diabetes mellitus (DM), bilateral ITAs in patients without DM, and possible avoidance of cardiopulmonary bypass (CPB) after 2003. RESULTS: Thirty-six percent of patients underwent conventional CABG: 20% had on-pump beating heart procedures and 44% had off-pump procedures, with 2.8 ± 1.0 anastomoses. Hospital mortality was 10.6% with improvement to 6.8% after 2003. Predictors for hospital death were left ventricular ejection fraction (LVEF) less than 0.40 (p = 0.042), use of CPB (p = 0.046), and postoperative need for continuous hemofiltration (p = 0.037). After follow-up of 49 ± 42 months, the overall survival rates were 76.9%, 60.0%, 43.9%, and 36.2% and the cardiac events-free rates were 77.0%, 70.1%, 55.9%, and 44.8% at 3, 5, 8, and 10 years, respectively, in the Kaplan-Meier model. A multivariate Cox proportional hazard model identified age older than 63 years (p = 0.014), DM (p = 0.036), and peripheral artery disease (PAD) (p = 0.044) as predictors for late death, and DM (p = 0.038) and LVEF less than 0.40 (p = 0.027) as predictors for late cardiac events. CONCLUSIONS: Although early outcomes have been improved by off-pump techniques, late outcomes are not satisfactory in patients who rely on HD and undergo CABG. To improve late outcomes we may need aggressive management of DM, PAD, and low LVEF in those patients.
The Annals of thoracic surgery 09/2012; · 3.74 Impact Factor
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ABSTRACT: In patients with acute type A aortic dissection (AAD), localization of the primary entry tear to be excluded is of major importance for intervention.
There are reliable indirect computed tomography (CT) findings to predict the entry site.
In 83 patients with type A AAD whose primary entry tears were identified surgically between 2003 and 2009, we retrospectively examined the diagnostic CT scans regarding pericardial effusion, the largest short-axial diameter of the aorta, widths of true and false lumens, and false lumen thrombosis at 6 levels of thoracic aorta from the aortic root to the descending aorta.
The primary entry sites identified intraoperatively were proximal ascending in 21 patients, middle ascending in 21, distal ascending in 21, arch in 17, and descending or unknown in 16. The multivariate logistic analysis revealed that pericardial effusion (odds ratio [OR]: 2.2, 95% confidence interval [CI]: 1.2-3.4, P < 0.001) and dilated ascending aorta (OR: 1.6, 95% CI: 1.1-2.4, P = 0.012) were the significant CT findings to predict the entry tear in the ascending aorta. It also revealed that the significant CT finding to predict the entry tear distal to the aortic arch was nonthrombosed false lumen in the descending aorta (OR: 1.2, 95% CI: 1.1-2.1, P = 0.048).
We can predict the primary entry site by the preoperative CT findings in patients with type A AAD, considering pericardial effusion, aortic diameter, widths of true and false lumens, and false lumen thrombosis at different anatomic levels.
Clinical Cardiology 04/2012; 35(8):500-4. · 2.15 Impact Factor
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ABSTRACT: There is limited information about the size change of a knitted Dacron graft (Gelseal™) used in the thoracic aorta. We evaluated the diameters of the Gelseal™ grafts at a long-term follow-up for 3.7 ± 1.3 years (1-5.9 years; median, 4.0 years), which were used for replacement of the ascending aorta in 59 patients with acute aortic dissection. The early and late dilatation rates (LDRs) of the prosthetic grafts were calculated retrospectively based on the graft diameter at the level equivalent to the ascending aorta on the pre-discharge computed tomography (CT) scans and follow-up CT scans performed every year after surgery. Immediately after surgery (15 ± 7 days), the early dilatation of the Gelseal™ grafts was 26.0 ± 6.0% with significant correlations with the number of post-operative days (R = 0.500, P = 0.003). At the follow-up for 3.7 ± 1.3 years, the LDR was 10.5 ± 6.6%, which was also significantly correlated with the number of the post-operative years (R = 0.608, P = 0.001). Linear regression analysis indicated that the annual dilatation rate was ≈ 3.23%. During the follow-up, we have experienced no redo surgery due to graft fracture or false aneurysm formation at the anastomosis sites associated with the graft dilatation. In conclusion, the Gelseal™ graft used in the ascending aorta demonstrates a small but continuous increase in the diameter, up to 5 years after implantation, without any adverse events.
Interactive cardiovascular and thoracic surgery 02/2012; 14(5):529-31.
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ABSTRACT: The mortality and morbidity rates are high after cardiac surgery in hemodialysis (HD)-dependent patients. To improve their outcomes, optimal perioperative managements should be discussed.
A retrospective analysis of 245 HD patients who underwent cardiac surgery between 1994 and 2007 was conducted. The basic management strategies were (1) low-potassium HD for 2 days before surgery, (2) only hemofiltration during cardiopulmonary bypass, and (3) start of regular intermittent HD on the first postoperative day. Continuous venovenous hemodiafiltration was applied only for patients with hemodynamic instability.
The causes of renal failure included diabetic (n = 89, 36%), glomerulonephritis (n = 49, 20%), and unknown (n = 75, 31%). The history of HD was 9.7 +/- 7.6 years. The operative procedures included coronary (n = 135), valve (n = 103), and others. The amount of intraoperative ultrafiltration was 6,123 +/- 324 mL during cardiopulmonary bypass for 197 +/- 67 minutes. Two hundred eight patients (85%) were managed with only intermittent HD, whereas 36 patients (15%) needed continuous venovenous hemodiafiltration. The use of continuous venovenous hemodiafiltration significantly declined during the year (26% before 2003 and 3% after 2003; p < 0.001). The amount of fluid removal on the first postoperative day was 1,297 +/- 81 mL. The hospital mortality was 9.7% with the causes including infection (n = 11), cardiac events (n = 6), gastrointestinal events (n = 5), and stroke (n = 2). A multivariate logistic regression analysis revealed that selection of intermittent HD or continuous venovenous hemodiafiltration was not related to the hospital mortality.
Simplified management only with intermittent HD can be safely performed in most HD-dependent patients undergoing cardiac surgery.
The Annals of thoracic surgery 11/2009; 88(5):1515-9. · 3.74 Impact Factor
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ABSTRACT: We investigated flow characteristics of right gastroepiploic arterial grafts, widely used to extend in situ arterial conduits in coronary artery bypass grafting.
Intraoperative transit-time measurements and postoperative angiographic findings were obtained for 111 patients undergoing coronary artery bypass grafting with gastroepiploic artery and bilateral internal thoracic arteries: mean, maximum, and minimum flows; pulsatility index; insufficiency rate; and differentiated index of early diastolic flow.
Favored target for gastroepiploic artery was posterior descending artery (106 patients, 95%). Patency rates were 91.0% for gastroepiploic artery, 98.2% for left internal thoracic artery, and 97.5% for right internal thoracic artery. There were four flow profiles of gastroepiploic arteries: A (systolic protruded), B (trapezoidal), C (sine waved), and D (diastolic-dominant biphasic). Functional gastroepiploic arteries showed A in 16 cases, B in 6, C in 31, and D in 48, with prevalence according to severity of stenosis in target coronary artery. Two occluded gastroepiploic arteries showed type A, and reverse or competitive flows were types A in 1, B in 1, C in 4, and D in 2. Relative to functional internal thoracic arteries, functional gastroepiploic arteries showed significantly lower minimum flow, higher insufficiency rate, and lower differentiated index of early diastolic flow.
Intraoperative transit-time flow profiles of patent in situ gastroepiploic arterial grafts were classified into four types, closely associated with disease severity of target coronary artery. Patent in situ gastroepiploic arterial grafts show more regurgitant flow and lower differentiated index of early diastolic flow than in situ internal thoracic arterial grafts.
The Journal of thoracic and cardiovascular surgery 10/2009; 138(3):669-73. · 3.41 Impact Factor
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ABSTRACT: Cardiac surgery in patients with severely atherosclerotic or porcelain ascending aorta is technically challenging, with markedly increased risk of atheroembolism. We describe a technique of meticulous crossclamping of a difficult aorta during short-term moderate hypothermic circulatory arrest.
From 1997 to 2007, we found 40 patients (mean age, 70 +/- 8 years), including 14 patients undergoing hemodialysis, whose preoperative computed tomographic and intraoperative epiaortic ultrasonographic scans revealed eggshell calcification (n = 15) or protruding atheromas (n = 25) of the ascending aorta. They underwent cardiac surgery (aortic, 31 patients; mitral, 3 patients; both, 5 patients; and coronary alone, 1 patient) by means of meticulous crossclamping during hypothermic circulatory arrest for 3.4 +/- 1.5 minutes at a rectal temperature of 29.0 degrees C +/- 2.3 degrees C. During hypothermic circulatory arrest, we performed only internal inspection to identify the safe location of crossclamping in 21 patients, whereas we required debridement of calcification or atheroma by using the Cavitron Ultrasonic Surgical Aspirator (Tyco Healthcare, Mansfield, Mass) for safe crossclamping in 19 patients.
By using this technique, no patients died during the hospital stay. Stroke occurred in 1 (2.5%) patient, and transient agitation occurred in 1 patient. Re-exploration for bleeding was required in 1 patient, and wound infection occurred in 2 patients. During follow-up, with a median time of 5.2 years, the overall survival rates were 100%, 90%, and 76% at 1, 3, and 5 years, respectively. Three patients required reoperations during the follow-up period because of pseudoaneurysm in 2 patients and prosthetic valve infection in 1 patient.
Short-term moderate hypothermic circulatory arrest is quite useful for safe aortic crossclamping after internal inspection or debridement in high-risk patients with a severely atherosclerotic aorta.
The Journal of thoracic and cardiovascular surgery 05/2009; 137(4):875-80. · 3.41 Impact Factor
