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Hendrick B Barner

Publications and source records attributed to Hendrick B Barner.

At least 19 recordsLinked to original sources
PubMed2006

Status of percutaneous coronary intervention and coronary artery bypass.

At present a rapid and profound change in myocardial revascularization has evolved from the work of Gruentzig. The recent technological advances have been so fast paced that there has not been ample time to fully assess each new facet of technology and pharmaceutics before another arrives. The interface between percutaneous intervention (PCI) and coronary artery bypass (CAB) is not well defined as previously so that continental, national and regional differences exist. The progress in PCI from balloon angioplasty to drug eluting stents has seen a progressive decline in restenosis and reintervention but relief of symptoms has not equaled that attained with CAB. Survival benefit for CAB over PCI has not been demonstrated in the many randomized clinical trials which are limited by selection of only 5-12% of potential patients so that higher risk patients and those with more extensive and complex coronary disease are excluded. These excluded patients are included in the registries where survival benefit for CAB over PCI is clearly evident. Situations less amenable to PCI include: left main disease; three vessel disease; vessels that are smaller, diffusely diseased or with distal lesions which are frequently associated with diabetes; ostial and bifurcation lesions; and coronary arteries that are tortuous, calcified or with very long lesions. It is in these situations that PCI does not provide revascularization equivalent to CAB. Surgeons must appreciate the success of PCI, acknowledge their reduced role in revascularization and strive to provide the best operation possible when the clinical situation demands it.

Angioplasty, Balloon, Coronary↗
PubMed2006

Valve replacement after T-grafting: "beating heart surgery".

Patent internal thoracic and radial artery T-graft will adequately perfuse the heart during reoperation. Five of 1,023 patients with prior T-grafting had aortic (3) or mitral valve redo operations in which the heart was allowed to beat (after an initial dose of cardioplegia) during the operation without clamping the patent T-graft. Rapid resumption of cardiac function after one dose of cardioplegia and no intraoperative or postoperative evidence of myocardial infarction indicated adequacy of perfusion without apparent myocardial injury. This approach avoids injury to the T-graft from dissection and clamping, saves time, and simplifies the operation.

Aged↗
PubMed2006

Chylothorax after internal thoracic artery harvest.

Chylothorax is a rare complication following coronary artery bypass graft surgery. We report a case of chylothorax that complicated a left internal thoracic artery harvest and review the literature regarding this subject.

Chylothorax↗
PubMed2006

Bland-White-Garland syndrome in pregnancy: reoperation of ALCAPA with an internal thoracic radial artery "Y"-graft.

Anomalous origin of the left coronary artery from the pulmonary artery is rare and more so in the adult. Reimplantation of the left main coronary into the aorta is successful in early life, but it may be more difficult in the adult who had a previous repair. We report a successful reoperation of anomalous origin of the left coronary artery from the pulmonary artery in an adult patient using a left internal thoracic and radial artery "Y"-graft. Composite arterial grafting has become an established and straight forward technique in coronary surgery, and it is appropriate and recommended for congenital lesions in adults and at any age if necessary.

Abnormalities, Multiple↗
PubMed2006

Prosthesis-patient mismatch after aortic valve replacement: impact of age and body size on late survival.

BACKGROUND: The purpose of this study was to identify patient subgroups in which prosthesis-patient mismatch most influenced late survival. METHODS: Over a 12-year period, 1,400 consecutive patients underwent bioprosthetic (933 patients) or mechanical (467) aortic valve replacement. Prosthesis-patient mismatch was defined as prosthetic effective orifice area/body surface area less than 0.75 cm2/m2 and was present with 11% mechanical and 51% bioprosthetic valves. RESULTS: With bioprosthetic valves, prosthesis-patient mismatch was associated with impaired survival for patients less than 60 years old (10-year: 68% +/- 7% mismatch versus 75% +/- 7% no mismatch, p < 0.02) but not older patients (p = 0.47). Similarly, with mechanical valves, prosthesis-patient mismatch was associated with impaired survival for patients less than 60 years old (10-year: 62% +/- 11% versus 79% +/- 4%, p < 0.005) but not older patients (p = 0.26). For small patients (body surface area less than 1.7 m2), prosthesis-patient mismatch did not impact survival with bioprosthetic (p = 0.32) or mechanical (p = 0.71) valves. For average-size patients (body surface area 1.7 to 2.1 m2), prosthesis-patient mismatch was associated with impaired survival with both bioprosthetic (p < 0.05) and mechanical (p < 0.005) valves. For large patients (body surface area greater than 2.1 m2), prosthesis-patient mismatch was associated with impaired survival with mechanical (p < 0.04) but not bioprosthetic (p = 0.40) valves. CONCLUSIONS: Prosthesis-patient mismatch had a negative impact on survival for young patients, but its impact on older patients was minimal. In addition, although prosthesis-patient mismatch was not important in small patients, prosthesis-patient mismatch negatively impacted survival for average-size patients and for large patients with mechanical valves.

Adult↗
PubMed2006

Invited commentary.

Explore the source record for details and available documents.

Angioplasty, Balloon, Coronary↗
PubMed2005

Impact of complete revascularization on long-term survival after coronary artery bypass grafting in octogenarians.

BACKGROUND: Complete revascularization is important in young patients undergoing coronary artery bypass grafting, but this principle remains less absolute in elderly patients. The purpose of this study was to determine how complete revascularization influenced long-term survival after coronary artery bypass grafting in octogenarians. METHODS: From 1986 to 2003, 500 consecutive patients 80 to 94 years of age underwent coronary artery bypass grafting. Complete revascularization was defined as placement of at least one graft to each of the three major vascular regions that included a 50% diameter lesion. Revascularization was complete in 400 (80%) patients and incomplete in 100 (20%) patients. Mean (+/- standard deviation) follow-up was 51 +/- 41 months and was 99% complete (2,102 total patient-years). RESULTS: Operative mortality was 8% +/- 2% (+/-95% confidence interval) and was statistically lower with complete (7% +/- 3%) versus incomplete (13% +/- 7%) revascularization (p < 0.05). Of 459 operative survivors, there were 261 late deaths. Multivariate regression analysis identified six independent predictors of late death: earlier operative year, male sex, peripheral or cerebrovascular disease, congestive heart failure, and incomplete revascularization (p < 0.03 for all). Excluding operative deaths, mean survival (Kaplan-Meier) was 82 months with complete revascularization compared with 65 months with incomplete revascularization (p < 0.008). Survival was 62% +/- 3% with complete versus 45% +/- 6% with incomplete revascularization at 5 years and 39% +/- 3% with complete versus 25% +/- 6% with incomplete revascularization at 8 years (p < 0.008). CONCLUSIONS: In octogenarians undergoing coronary artery bypass grafting, complete revascularization correlated with improved long-term survival, increasing mean survival by almost 25% compared with incomplete revascularization.

Age Factors↗
PubMed2005

Radial artery grafts in women: utilization and results.

BACKGROUND: Despite a known survival benefit with the use of the left internal mammary artery, it is used less frequently in women when compared with men. This study evaluated the hypotheses that the radial artery graft is used less frequently in women compared with men, that the radial artery is smaller in women compared with men, and that the use of the radial artery influences operative mortality and long-term survival in women. METHODS: The use of a radial artery graft was evaluated in 2,633 patients who underwent isolated coronary artery bypass. Radial artery size and flow were compared in 207 patients who had intraoperative radial artery diameter and flow measurements. Propensity scoring was utilized to compare short- and long-term outcomes in a matched cohort of 588 women. RESULTS: Of 862 women (33%) who had isolated coronary artery bypass grafting, only 301 (35%) received a radial artery graft versus 44% of men (786 of 1,771, p < 0.001). Radial artery size and flow were significantly less in women. Operative mortality was not different between women with a radial artery graft and women without; however, 5-year survival was significantly better in women with a radial artery graft than in those without. CONCLUSIONS: Women received fewer radial artery grafts than men. Radial artery size and flow were significantly less in women than in men. Use of a radial artery graft did not influence operative mortality among women. However, 5-year survival among women who received a radial artery graft was significantly better than among women who did not.

Aged↗
PubMed2005

Phenylephrine to increase blood flow in the radial artery used as a coronary bypass conduit.

OBJECTIVE: The radial artery has more smooth muscle in its wall than the other arterial conduits and is known to be vasospastic. Because it is frequently necessary to use vasoconstrictors early after coronary bypass surgery we investigated the effects of phenylephrine on conduit flow in this setting. METHODS: Thirty patients undergoing coronary artery bypass with all arterial conduits in which the radial artery was used as a T-graft were randomly assigned to receive intravenous infusions of normal saline (n = 10); nitroglycerin, 0.5 microg x kg x min (n = 11); or nicardipine, 0.5 microg x kg x min (n = 9), beginning early in the operation. After discontinuation of cardiopulmonary bypass and achievement of stable hemodynamics, control measurements were obtained, and this was followed by phenylephrine infusion to achieve a 20% increase in mean arterial pressure, after which the measurements were repeated. RESULTS: Mean radial artery flow increased similarly in all groups: normal saline, 40% +/- 25%; nicardipine, 37% +/- 27%; nitroglycerin, 48% +/- 36% (P = .533). Comparable changes occurred in arterial pressure and systemic vascular resistance, whereas the cardiac index remained unchanged. CONCLUSION: Radial artery blood flow increases when the mean arterial pressure is increased with phenylephrine. There was no evidence of a conduit vasoconstrictive effect, which could limit or reduce conduit flow. Vasoconstriction with phenylephrine is appropriate to provide adequate perfusion pressure for radial artery grafts.

Blood Flow Velocity↗
PubMed2004

Long-term neurologic hand complications after radial artery harvesting using conventional cold and harmonic scalpel techniques.

BACKGROUND: The purpose of this study was to determine the incidence of neurologic hand complications after radial artery harvesting and to compare the harmonic scalpel versus conventional cold scalpel technique. METHODS: From 1995 to 2000, 786 radial arteries were harvested from 782 patients for coronary artery bypass grafting. From 1995 to 1997, the conventional cold scalpel technique was used (422 patients), and from 1998 to 2000, the harmonic scalpel was used (360 patients). Mean follow-up was 4.2 +/- 2.1 years and was 90% complete. Symptoms included thumb weakness or numbness, tingling, or pain in the hand. RESULTS: The incidence of neurologic hand complications was similar with both techniques (11.2% +/- 3.5% cold, 11.0% +/- 3.6% harmonic, p > 0.95), and in 19% (13 of 67 with symptoms) there was complete resolution within 1 year. Symptoms persisted long-term in 9.0% +/- 3.2% cold scalpel and 9.0% +/- 3.3% harmonic scalpel patients (p > 0.81), but were considered a "constant and significant source of discomfort" in only 0.6% +/- 0.9% cold scalpel and 1.4% +/- 1.3% harmonic scalpel patients (p > 0.41). CONCLUSIONS: The incidence of adverse neurologic outcomes causing significant long-term discomfort in the hand was low using either the cold scalpel or harmonic scalpel technique. However, a significant number of patients had neurologic hand symptoms in both groups, and this should be included when discussing operative risks with the patient.

Aged↗
PubMed2004

Repair of ischemic mitral regurgitation does not increase mortality or improve long-term survival in patients undergoing coronary artery revascularization: a propensity analysis.

BACKGROUND: The purpose of this study was to compare operative mortality and midterm outcome of patients with ischemic mitral regurgitation (MR) undergoing either coronary artery bypass grafting (CABG) alone or CABG with mitral valve (MV) repair. METHODS: From 1996 to 2001, 51 consecutive patients underwent CABG with MV repair for ischemic MR. All patients in this group were matched to similar patients with ischemic MR undergoing CABG alone during the same 6-year period using propensity analysis (considering 24 covariates, including severity of MR and New York Heart Association [NYHA] class). RESULTS: Propensity score matching yielded 51 closely matched control patients. Preoperative MR severity was 3+ or 4+ in 94% of CABG with MV repair and 96% of CABG-alone patients, and 86% of patients in each group were NYHA class III or IV. Operative mortality was 3.9% +/- 2.8% in both groups. Survival was also similar between CABG with MV repair and CABG alone at 1 year (84% +/- 5% versus 82% +/- 5%) and 3 years (70% +/- 7% versus 71% +/- 7% (p = 0.43). Among survivors, NYHA class improved at follow-up (50 +/- 20 months) from 3.4 +/- 0.7 to 1.7 +/- 1.0 for CABG with MV repair (p < 0.001) and from 3.4 +/- 0.7 to 1.8 +/- 1.0 for CABG alone (p < 0.001). CONCLUSIONS: Operative mortality, midterm survival, and late functional class were similar between two well-matched groups of patients undergoing CABG for ischemic MR, differing only in the addition of MV repair. Whereas MV repair can be added safely to CABG in this group of high-risk patients without increasing mortality, its impact on late survival and functional class may be limited.

Aged↗
PubMed2004

Flow dynamics of the internal thoracic and radial artery T-graft.

BACKGROUND: Complex use of arterial conduits has resurrected concerns about the adequacy of conduit flow. The T-graft is the extreme example of this trend. Our purpose was to identify the limitation of single source inflow and to compare flow capacity with completion coronary flow. METHODS: Between February 1999 and November 2001, 372 patients underwent total arterial revascularization with the T-graft alone. Intraoperative flows were recorded for each limb of the T-graft before and after distal anastomoses in 204 patients. Independent predictors of T-graft flow were identified by multivariate analysis. RESULTS: Free flow for the radial arterial (RA) limb was 161 +/- 81 mL/min, the internal thoracic artery (ITA) limb 137 +/- 57 mL/min (combined 298 +/- 101 mL/min) versus simultaneous limb flow of 226 +/- 84 mL/min giving a flow restriction of 24% +/- 14%. Completion coronary flow was 88 +/- 49 mL/min for the RA, 60 +/- 45 mL/min for the ITA, and 140 +/- 70 mL/min for both limbs simultaneously to give a flow reserve (vs simultaneous free flow) of 160% or 1.6. Independent predictors of completion RA limb flow are RA proximal diameter (p = 0.005), number of anastomoses (p = 0.018), and target stenosis (p = 0.005). CONCLUSIONS: A flow reserve of 1.6 compares favorably with an ITA flow reserve of 1.8 at 1-month postoperatively and 1.8 for both the ITA T-graft and the ITA/RA T-graft at 1-week postoperatively as reported by others. Proximal RA diameter and competitive coronary flow influence completion T-graft flow. These data quantitate the limitation of single source inflow of the T-graft configuration and support its continued use.

Aged↗
PubMed2003

Radial artery patency: are aortocoronary conduits superior to composite grafting?

BACKGROUND: The radial artery (RA) can be used as either an aortocoronary (RA-Ao) or composite graft (T graft). Optimum use for the RA has yet to be established. We compared RA patency with these two techniques. METHODS: Between October 1993 and June 2001, 1505 patients underwent coronary artery bypass grafting using the RA as either a composite (n = 1022) or RA-Ao graft (n = 483). Angiograms performed on 203 (13.5%) patients with signs or symptoms of ischemia at an average of 26.1 +/- 18.5 months postoperatively were reviewed. RESULTS: Patients with RA-Ao grafts had a greater incidence of postoperative angiography versus patients with composite grafts (19% versus 11%; p < 0.01). Patients receiving T grafts had a greater number of anastomoses per patient (4.1 +/- 0.6 versus 3.0 +/- 1.0; p < 0.01) and a higher incidence of total arterial revascularization (100% versus 41%; p < 0.01). Regardless of grafting strategy, patency was significantly worse for targets of the right coronary artery (58% T graft; 67% RA-Ao; p < 0.01 for both) and for targets with less than or equal to 70% stenosis (59% T graft; 57% RA-Ao; p < 0.01 for both). The site of proximal anastomosis failed to effect RA patency (relative risk, 1.2; 95% confidence interval, 0.7 to 1.8; p = 0.50). CONCLUSIONS: The site of the proximal anastomosis does not appear to influence patency. Both RA-Ao and composite conduits are sensitive to target location and stenosis. Advantages of composite grafting include greater conduit length and minimizing aortic manipulation at the expense of increased complexity and the potential for hypoperfusion. These factors should be considered when choosing an RA grafting strategy.

Aged↗
PubMed2002

Coronary revascularization in the 21st century. Emphasis on contributions by Japanese surgeons.

The first three decades of coronary artery surgery have provided the foundation for the next century of this evolution. It is apparent that a multitude of events including the development of cardioplegia, improving surgical instrumentation, technological advances including endoscopic approaches and computer assisted robotics and biologic discoveries such as the role of the endothelium have provided the underpinnings for improved surgical outcomes. However, the single most important determinant of late results is the type of bypass conduit used for grafting. Thus, use of the left internal thoracic artery (ITA) grafted to the left anterior descending coronary is a more important determinant of survival than is any other factor (progression of coronary artery disease, increased age, poor left ventricular function, diabetes, female gender and off-pump operations). Use of two ITAs provides further benefit and it is likely that three or more arterial conduits will be shown to be advantageous in this regard in due time. Japanese cardiothoracic surgeons have made significant contributions to the continuing evolution of coronary bypass surgery and particularly to the advance of arterial conduits. This report will address those contributions to this evolution.

Coronary Artery Bypass↗
PubMed2002

Remodeling of arterial conduits in coronary grafting.

In the initial decade of coronary surgery, serial angiography of internal thoracic artery grafts revealed increased caliber in some, decreased caliber in others, and "string sign" in a few, which was occasionally documented to be reversible. Although we speculated on possible causes of these changes, it was not until discovery of the endothelial role in modulating arterial diameter to maintain shear stress in a narrow range that we began to gain insight into the mechanisms responsible for remodeling of the arterial wall. This review provides a glimpse of the physiology and biology of arterial remodeling and summarizes observations on the various arterial conduits when subjected to flow alterations.

Animals↗