Biomedical subjects

R Mohr

Publications and source records attributed to R Mohr.

At least 19 recordsLinked to original sources

PubMed2006

Initiation of shape-memory effect by inductive heating of magnetic nanoparticles in thermoplastic polymers.

In shape-memory polymers, changes in shape are mostly induced by heating, and exceeding a specific switching temperature, T(switch). If polymers cannot be warmed up by heat transfer using a hot liquid or gaseous medium, noncontact triggering will be required. In this article, the magnetically induced shape-memory effect of composites from magnetic nanoparticles and thermoplastic shape-memory polymers is introduced. A polyetherurethane (TFX) and a biodegradable multiblock copolymer (PDC) with poly(p-dioxanone) as hard segment and poly(epsilon-caprolactone) as soft segment were investigated as matrix component. Nanoparticles consisting of an iron(III)oxide core in a silica matrix could be processed into both polymers. A homogeneous particle distribution in TFX could be shown. Compounds have suitable elastic and thermal properties for the shape-memory functionalization. Temporary shapes of TFX compounds were obtained by elongating at increased temperature and subsequent cooling under constant stress. Cold-drawing of PDC compounds at 25 degrees C resulted in temporary fixation of the mechanical deformation by 50-60%. The shape-memory effect of both composite systems could be induced by inductive heating in an alternating magnetic field (f = 258 kHz; H = 30 kA x m(-1)). The maximum temperatures achievable by inductive heating in a specific magnetic field depend on sample geometry and nanoparticle content. Shape recovery rates of composites resulting from magnetic triggering are comparable to those obtained by increasing the environmental temperature.

Journal Article↗

PubMed2003

Technical aspects of harvesting the radial artery with the harmonic scalpel.

BACKGROUND: Harvesting the radial artery (RA) with ultrasonic dissection with the Harmonic Scalpel reduces spasm induced by surgical handling. Topical exposure to phentolamine methanesulphonate (Regitine) exerts an additional effect of vasodilatation. METHODS: Between January and December 2002, the RA was harvested as a pediculated vessel with the Harmonic Scalpel in 145 consecutive patients undergoing myocardial revascularization. A fasciotomy of the pedicle was performed after harvest ing. A composite graft with the reverse free RA on the in situ left internal thoracic artery (ITA) was prepared before the construction of distal coronary anastomoses. The RA was then placed in a syringe filled with Regitine (0.07 microg/mL) for 10 minutes. \par RESULTS: The mean number of grafts/patient was 3.0. The mean number of RA anastomoses was 2.0/patient. Left ITA free flow was 105 +/- 34 mL/min. Regitine increased the RA free flow from 60 +/- 35 mL/min to 82 +/- 30 mL/min (P <.05). Fourteen patients underwent postoperative coronary angiography. All RA anastomoses were patent. CONCLUSION: The compound effect of RA harvesting with the Harmonic Scalpel and topical treatment with the alpha- blocking agent Regitine increases the RA free flow and significantly decreases intraoperative spasticity.

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PubMed2003

Midterm results of routine bilateral internal thoracic artery grafting.

BACKGROUND: Skeletonized dissection of the internal thoracic artery (ITA) decreases the occurrence of sternal devascularization, thus decreasing the risk of postoperative sternal complications in patients undergoing bilateral ITA grafting. METHODS: From April 1996 to July 1999, 1000 consecutive patients underwent bilateral skeletonized ITA grafting. Of the 770 male and 230 female patients, 420 were older than 70 years, and 312 had diabetes. RESULTS: Operative mortality was 3.3%. Follow-up (40-78 months) revealed 79 late deaths, and the Kaplan-Meier 6-year survival rate was 88%. Cox regression analysis revealed increased overall mortality (early and late) in patients with preoperative congestive heart failure (risk ratio [RR], 2.13; 95% confidence interval [CI], 1.31-3.45), in patients with peripheral vascular disease (RR, 5.52; 95% CI, 3.31-9.19), and in patients older than 70 years (RR, 2.18; 95% CI, 1.37-3.47). Early postoperative morbidity included sternal infection (2.2%), cerebrovascular accident (1.6%), and perioperative myocardial infarction (1%). Multiple regression analysis showed repeat operation (odds ratio [OR], 7.5; 95% CI, 1.77-31.6) and chronic obstructive pulmonary disease (OR, 3.6; 95% CI, 1.27-10.75) to be independent predictors of sternal infection. During follow-up, angina returned in 95 patients, 24 of whom required reintervention (20 cases of percutaneous balloon angioplasty and 4 reoperations). Postoperative coronary angiography performed in 87 patients revealed an ITA patency rate of 91%. CONCLUSIONS: Bilateral skeletonized ITA grafting is associated with satisfactory early and midterm results. We do not recommend the use of this surgical technique in patients with chronic obstructive pulmonary disease.

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PubMed2002

Pretreatment with alpha-adrenergic blockers for prevention of radial artery spasm.

BACKGROUND: Radial artery (RA) conduits are prone to early vasospasm. Current intraoperative treatment with papaverine fails to inhibit postoperative RA constriction. Pretreatment with topical a-antagonist solutions can inhibit RA vasoconstriction and cause dilatation for a longer period than achieved with papaverine. METHODS: In 10 patients undergoing myocardial revascularization, the radial artery was harvested as a skeletonized vessel. A composite graft with reverse free RA on an in situ left internal thoracic artery was prepared before construction of distal coronary anastomoses. The RA pedicle was then put in a small syringe filled with Regitine (phentolamine methansulphonic, 0.07 mg/mL) ("Jacuzzi") and warmed by immersing the container in a warm saline bath for 8 to 15 minutes. The RA free flow was measured before and after topical treatment with Regitine. RESULTS: The mean number of grafts per patient was 2.9 (range 2 to 4). The mean number of radial anastomoses was 1.8 per patient. Left internal thoracic artery free flow was 110 +/- 29 mL/min. Regitine increased radial free flow from 49 +/- 35 to 77 +/- 30 mL/min (p < 0.01). Five patients underwent postoperative coronary angiography. All radial anastomoses were patent. CONCLUSIONS: Topical treatment of RA with Regitine increases RA free flow and is an effective intraoperative means of decreasing RA spasticity.

Adrenergic alpha-Antagonists↗

PubMed2001

Effect of age on outcome of bilateral skeletonized internal thoracic artery grafting.

BACKGROUND: Elderly patients are considered to be at higher risk for coronary artery bypass grafting. Surgical techniques of arterial myocardial revascularization without vein grafts were primarily reserved for the young. This report evaluates the impact of age on the outcome of 634 consecutive patients who underwent double skeletonized internal thoracic artery grafting between April 1996 and December 1997. METHODS: Patients were stratified into five age groups: One hundred ninety-six were less than 60 years of age, 98 between 60 and 65 years, 132 between 65 and 70 years, 116 between 70 and 75 years, and 92 were older than 75 years. The groups did not differ with regard to preoperative risk factors. RESULTS: Hospital mortality was 2.5% (n = 16). Mortality of urgent and elective operations was 1.6%, and that of emergency operations was 9.7% (p < 0.001). There were 7 (1.1%) myocardial infarctions, 9 strokes (1.4%), and 10 deep sternal wound infections (1.6%). Using the Mantel-Haenszel test, there was no relation between age and hospital mortality, myocardial infarctions, strokes, or sternal infections. A correlation was found between advanced age and early unfavorable events (6.7%, 7.2%, 12.9%, 15.5%, and 15.2% in corresponding age groups, p < 0.003), and late mortality (0.6%, 1%, 1.5%, 4.3%, and 9.8%, respectively, p < 0.01). However, early return of angina was lower (2.6%, 1%, 0.8%, 0.9%, and 0%, p < 0.06). CONCLUSIONS: This retrospective, nonrandomized study suggests that older age is not a risk factor for operative mortality in patients undergoing coronary artery bypass grafting with double skeletonized internal thoracic arteries. Apart from avoiding morbidity associated with leg incisions, older patients showed an interesting trend toward lower rates of angina return. Older patients, however, sustained increased perioperative morbidity and late mortality rates.

Actuarial Analysis↗

PubMed2001

Arterial myocardial revascularization with in situ crossover right internal thoracic artery to left anterior descending artery.

BACKGROUND: The extra length obtained by skeletonizing the internal thoracic arteries (ITAs) enables versatile use of in situ bilateral ITAs for coronary artery bypass grafting, as the longer skeletonized right ITA more easily reaches the anastomotic site on the left anterior descending coronary artery. METHODS: Between April 1996 and November 1999, 365 consecutive patients underwent revascularization with bilateral in situ ITAs (29% of 1,250 grafting procedures performed with both ITAs in our department during this period). The right ITA was routed anterior to the aorta to graft the left anterior descending coronary artery, and the in situ left ITA was used to graft circumflex branches. Right coronary artery branches were grafted with right gastroepiploic artery or saphenous vein graft. The right ITA crossed the midline above the aorta at the most cranial point to avoid damage in case of a repeat sternotomy in the future. RESULTS: The operative mortality rate was 2.2% (8 patients). Postoperative morbidity included seven strokes (1.9%), eight sternal wound infections (2.2%), and four perioperative myocardial infarctions (1.1%). Follow-up (6 to 49 months) of 97% of hospital survivors showed a return of angina in 3%. Postoperative coronary angiography (22 patients) revealed a 95% patency rate of both ITAs. One-year and 4-year survival rates (Kaplan-Meier) were 95% and 92.4%, respectively. Important predictors of an early unfavorable event were chronic obstructive pulmonary disease, old age (> or = 70 years), emergency operation, and diabetes. Chronic obstructive pulmonary disease was the only independent predictor of sternal wound infection (odds ratio, 15; 95% confidence interval, 2.8 to 80). It also predicted decreased late survival (hazard ratio, 8.3; 95% confidence interval, 3 to 21.5). CONCLUSIONS: With skeletonized dissection of ITAs, the right ITA easily reaches the left anterior descending coronary artery for left-sided arterial revascularization with in situ bilateral ITAs. This procedure is safe, but we recommend avoiding its use in patients with chronic obstructive pulmonary disease.

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PubMed2001

Interaction between paracrine tumor necrosis factor-alpha and paracrine angiotensin II during myocardial ischemia.

OBJECTIVES: The purpose of this study was to explore interactions between paracrine angiotensin II (Ang-II) and tumor necrosis factor-alpha (TNF-alpha) during myocardial ischemia. BACKGROUND: Ischemic myocardium releases significant amounts of TNF-alpha. This paracrine release correlated with postischemic myocardial injury. Other studies showed myocardial protection obtained by the use of angiotensin-converting enzyme inhibitors (i.e., captopril) and the Ang-II type 1 receptor antagonist losartan after ischemia. The possibility that these agents decrease TNF-alpha synthesis has not yet been investigated. METHODS: Using the modified Langendorff model, isolated rat hearts underwent either 90 min of nonischemic perfusion (control group) or 1 h of global cardioplegic ischemia. In both groups, either captopril (360 micromol/liter) or losartan (182.2 micromol/liter) was added before ischemia. The hearts were assayed for messenger ribonucleic acid (mRNA) expression and effluent TNF-alpha levels. In addition, cardiac myocytes were incubated in cell culture with Ang-II. RESULTS: After ischemia, TNF-alpha mRNA expression intensified from 0.63 +/- 0.06 (control group) to 0.92 +/- 0.12 (p < 0.03), and effluent TNF-alpha levels were 711 +/- 154 pg/ml. The TNF-alpha mRNA expression declined to 0.46 +/- 0.07 (p < 0.01) and 0.65 +/- 0.08 (p < 0.02) in captopril- and losartan-treated hearts, respectively. Effluent TNF-alpha was below detectable levels. Concentrations of TNF-alpha in supernatants of incubated cardiac myocytes treated with 10 and 50 nmol/liter of Ang-II were 206.0 +/- 47.0 pg/ml and 810 +/- 130 pg/ml, respectively (p < 0.004). When pretreated with 700 micromol/liter of losartan, TNF-alpha was below detectable levels. CONCLUSIONS: This study presents an original explanation for previously reported myocardial protection after ischemia, obtained by the use of captopril and losartan. These drugs reduce TNF-alpha synthesis, providing strong evidence of active interactions between paracrine TNF-alpha and Ang-II in the evolution of the ischemic cascade.

Angiotensin II↗

PubMed2001

Vasoactive response of different parts of human internal thoracic artery to isosorbide-dinitrate and nitroglycerin: an in-vitro study.

OBJECTIVE: The left internal thoracic artery (LITA) is the most important graft for coronary artery bypass grafting (CABG). Its distal region is, however, prone to vasospasm. The effect of nitroglycerin (NTG) and isosorbide-dinitrate (ISDN) on different segments of this region was studied. METHODS: Rings of three segments of the LITA were studied: 6-9 mm proximal to the bifurcation (part A); 1-3 mm proximal to the bifurcation (part B); and 3-6 mm distal to the bifurcation (part C). After baseline, maximal contraction of the rings was achieved using 60 mmol/l of KCl, they were exposed to increasing doses of ISDN and NTG (10-100 microg/ml), and dose-response curves were recorded. RESULTS: The contractile response of part A to KCl was significantly lower than that of parts B and C (1.87+/-0.25 versus 4.05+/-0.39 and 7.64+/-0.54 g, respectively; P<0.001). Both nitrates inhibited the contractile response in a concentration-dependent manner. The relaxing effects of both nitrates on part A was most pronounced (P<0.01), with the effect of ISDN being higher than that of NTG (P<0.01). CONCLUSIONS: The region 6-9 mm proximal to the LITA bifurcation is less prone to vasospasm, and has greater relaxation responses to ISDN and NTG than the more vasospastic distal parts of the LITA. We recommend avoiding the use of the very distal part of this artery during CABG, and to use high doses of ISDN rather than NTG as an anti-spastic measure.

Analysis of Variance↗

PubMed2001

Protamine cardiotoxicity and nitric oxide.

OBJECTIVES: The purpose of this study is to assess the role of the nitric oxide (NO) pathway in protamine-induced cardiotoxicity and to formulate a possible explanation for this adverse effect. METHODS: Isolated rat hearts were perfused by Krebs--Henseleit (KH) solution using a modified Langendorff model. They were randomized into three groups: A, 40 min perfusion with KH solution; B, 20 min perfusion with KH solution and 20 min with protamine; C, as B but Ng-monomethyl-L-arginine (L-NMMA), a non-selective inhibitor of the NO pathway, was added during 40 min of the perfusion period. Left ventricular (LV) function was measured every 10 min. NO and tumor necrosis factor-alpha (TNF) were detected in the effluent from the coronary sinus (CS) and in the supernatant of the cardiac myocytes culture. Nitric oxide synthases (NOS) mRNA levels were determined in groups A and B from LV samples at baseline and after 40 min of perfusion. RESULTS: We found that protamine at a dose of 12 microg/ml causes significant depression of LV function (decreased peak systolic pressure to 22.5+/-3.2% and dP/dt max to 22.9+/-3.1%). L-NMMA did not prevent protamine cardiotoxicity. NOS mRNA was not detected from LV samples in any group. The NO in the effluent from the CS and from the supernatant of the cardiomyocytes culture was below detectable levels. However, a significant amount of TNF was measured in the effluent from the CS (108+/-17 pg/min for group B and 117+/-13 pg/min for group C) and in the supernatant of the cardiomyocytes culture (65+/-21 pg/ml). CONCLUSIONS: This study suggests that direct protamine-induced cardiotoxicity does not depend on the NO pathway. Our finding that protamine induced TNF release by cardiomyocytes can shed new light on the understanding of protamine cardiotoxicity.

Animals↗

PubMed2001

Composite arterial grafting with double skeletonized internal thoracic arteries.

OBJECTIVES: Composite arterial grafting is a surgical technique for arterial myocardial revascularization, in which free arterial conduits are proximally anastomosed end-to-side to an intact internal thoracic artery (ITA). This report describes technical aspects and results of composite grafting using bilateral skeletonized ITAs. METHODS: From April 1996 to February 1999, 1057 patients underwent coronary artery bypass grafting (CABG) using bilateral skeletonized internal thoracic arteries. In 600 of them (57%), composite arterial grafting was performed. There were 452 men and 148 women. The mean age was 69 +/- 7 years. Two-hundred and six patients (34%) were diabetics, 84 (14%) had severe left ventricular dysfunction (ejection fraction of < 35%), and 26 (4.3%) underwent emergency operations. In 574 patients, the right ITA was used as a free graft connected to the in-situ left ITA. In 26, the free left ITA was attached to the in-situ right ITA, and in 38, mini-composite grafts (free distal left ITA on the left ITA, or free distal right ITA on the right ITA) were constructed. The average number of grafts was 3.0/patient (range, 2--6). RESULTS: The operative mortality was 2.8% (n = 17), and there were ten (1.7%), deep sternal wound infections. The mean follow-up was 25 months (range, 14--36 months). The 3-year survival was 92.5%. Ninety-seven percent of the surviving patients were angina-free. CONCLUSIONS: We currently perform this surgery routinely in most patients referred for CABG, and regard bilateral skeletonized internal thoracic arteries as the most appropriate arterial conduits for the composite technique.

Adult↗

PubMed2001

Bilateral skeletonized internal thoracic artery grafts in patients with diabetes mellitus.

OBJECTIVE: Increased risk of deep sternal infections has prohibited routine bilateral internal thoracic artery grafting in diabetic patients. The technique for harvesting the skeletonized internal thoracic artery provides the potential to minimize this risk. The purpose of this study was to compare the outcome of bypass grafting with bilateral skeletonized internal thoracic arteries in diabetic and nondiabetic patients. METHODS: From May 1996 to April 1998, 231 consecutive diabetic and 534 nondiabetic patients underwent bilateral skeletonized internal thoracic artery grafting. Mean age was 66 years. Compared with the nondiabetic group, the diabetic group comprised more women (29% vs 18%, P =.001), had a greater prevalence of hypertension (53% vs 44%, P =.019) and congestive heart failure (20% vs 14%, P =.016), but a lower prevalence of preoperative acute myocardial infarction (26% vs 34%, P =.027). RESULTS: Operative mortality of diabetic patients was comparable with that of nondiabetic patients (3% vs 2.6%). The two groups also had similar occurrences of deep sternal infection (2.6% vs 1.7%, respectively, P =.40). Deep sternal infection was significantly more prevalent in obese, diabetic women (3/20 = 15%) than in diabetic patients without this combination of risk factors (3/211 = 1.4%, P <.0001) (odds ratio 11.1, confidence interval 2.1-59.4). Diabetic patients also had a higher incidence of stroke (3.5% vs 0.9%, P =.014). Three-year actuarial survival of diabetic patients was lower (91.3% vs 94.7%, P =.083). CONCLUSIONS: Bilateral skeletonized internal thoracic artery grafting is a good surgical revascularization option in diabetic patients. Operative mortality and prevalence of sternal infection are comparable with those of nondiabetic patients. However, the risk of sternal infection in obese diabetic women is high, and for them we advocate the use of a single artery instead of bilateral internal thoracic arteries.

Aged↗

PubMed2001

Protamine-induced cardiotoxicity is prevented by anti-TNF-alpha antibodies and heparin.

BACKGROUND: We investigated the role of tumor necrosis factor alpha (TNF-alpha) in protamine-induced cardiotoxicity and the possibility of preventing or decreasing this effect by anti TNF-alpha antibodies and heparin. METHODS: Isolated rat hearts were perfused for 60 min with Krebs-Henseleit solution (KH). The control group was perfused with KH alone, the KH > protamine > KH group was treated from the 20th to the 40th minute with protamine, and the KH + anti-TNF > protamine + anti-TNF > KH + anti-TNF group was treated the same as the KH > protamine > KH group but with anti-TNF-alpha antibodies added throughout perfusion. The KH + heparin > protamine + heparin > KH + heparin group was treated the same as the KH > protamine > KH group but with heparin added to KH throughout perfusion. The KH > protamine > KH + heparin was perfused the same as the KH> protamine > KH group but with heparin added to KH for the last 20 min. Left ventricular (LV) function and coronary flow were measured every 10 min. TNF-alpha was measured in the coronary sinus effluent. Left ventricular TNF messenger RNA was determined in the control and KH > protamine > KH groups at baseline and after the 40-min perfusion. RESULTS: Protamine caused a significant decrease of peak systolic pressure and dP/dt (to 25% of baseline). Significant amounts of TNF-alpha in the effluent in the KH > protamine > KH group (102.3 +/- 15.5 pg/min) and TNF messenger RNA expression in left ventricular samples were detected. TNF-alpha was below detectable concentrations in the control, KH + anti-TNF > protamine + anti-TNF > KH + anti-TNF, and KH + heparin > protamine + heparin > KH + heparin groups. TNF-alpha concentrations correlated with depression of LV peak systolic pressure (r = 0.984; P = 0.01) and first derivate of the increase of LV pressure (r = 0.976; P = 0.001). Heparin improved LV recovery and decreased protamine-induced TNF-alpha release (KH > protamine > KH + heparin group). CONCLUSIONS: Anti-TNF-alpha antibodies and heparin prevent protamine-induced TNF-alpha release and depression of LV function. Heparin improves protamine-induced depression of cardiac function.

Animals↗

PubMed2000

Protamine induces vasorelaxation of human internal thoracic artery by endothelial NO-synthase pathway.

BACKGROUND: Protamine is commonly used in cardiac surgery to reverse the anticoagulant effects of heparin. We investigated the role of different nitric oxide synthase pathways in the response of the human internal thoracic artery to protamine and evaluated whether heparin could prevent this effect. METHODS: A tension-recording method was used to obtain baseline measurements of contractions of human internal thoracic artery rings achieved with norepinephrine. Isolated internal thoracic artery rings were suspended in two organ chambers. One contained Krebs-Henseleit solution and served as control. The other contained a heparin or Nomega-Nitro-L-arginine (L-NAM, an inhibitor of both endothelial and inducible nitric oxide synthase) or a specific inhibitor of inducible nitric oxide synthase, aminoguanidine. Increasing doses of protamine were added to both chambers and dose-response curves were obtained. RESULTS: Protamine was found to relax contracted internal thoracic arteries 56% +/- 4.7% of baseline measurements in a concentration-dependent manner. When L-NAM was added, protamine caused only a slight decrease of tension. There were no differences in the relaxing effect of protamine in the presence of aminoguanidine or heparin. CONCLUSIONS: Protamine induces nitric oxide-dependent relaxation of the internal thoracic artery by activation of endothelial nitric oxide synthase pathway. Heparin could not prevent this relaxing effect of protamine.

Coronary Artery Bypass↗

PubMed2000

Low-molecular-weight heparin for prosthetic heart valves: treatment failure.

There is no adequate substitute therapy for patients with prosthetic heart valves, in whom anticoagulation with warfarin or unfractionated heparin must be withheld. In the literature there are several reports describing successful treatment with low-molecular-weight heparin in patients with prosthetic heart valves. We report two cases of low-molecular-weight heparin treatment failure resulting in thrombosed prosthetic heart valves with stormy clinical presentations, who underwent successful valve replacements.

Adult↗

PubMed2000

Technical aspects of double-skeletonized internal mammary artery grafting.

BACKGROUND: Bilateral internal mammary artery (IMA) grafting is performed to provide complete arterial myocardial revascularization with the intention of decreasing postoperative return of angina and the need for reoperation. We present here technical views of double-skeletonized IMA grafting, and evaluate its clinical outcome. METHODS: Skeletonized IMA is harvested gently with scissors and silver clips, without use of cauterization, and embedded in a small syringe filled with papaverine. Three strategies for arterial revascularization were employed in 762 consecutive patients: (1) the cross arrangement (242 patients, 32%), where the in situ right internal mammary artery (RIMA) is used for the left anterior descending artery (LAD), in situ left internal mammary artery (LIMA) to circumflex marginal branches and the gastroepiploic artery for the right coronary artery (RCA); (2) the composite arrangement (476 patients, 62%), where free IMA is attached end-to-side to the other in situ IMA; and (3) the natural arrangement (44 patients, 6%), where the in situ RIMA is connected to the RCA and in situ LIMA to LAD. Mean age was 66 years (range 30 to 92). Two hundred ninety-two patients (38%) were older than 70, and 229 (30%) were diabetic. RESULTS: Operative mortality was 2.5% (n = 19). The mortality of urgent and elective cases was 1.2% (8 of 663), and that of emergency operation was 11% (11 of 99). There were 9 (1.2%) perioperative myocardial infarctions, and 10 patients (1.3%) sustained strokes. Sternal wound infection occurred in 14 (1.8%). CONCLUSIONS: The three strategies described here provide the surgeon with the versatility required for arterial revascularization with bilateral IMAs in most patients referred for coronary artery bypass grafting.

Adult↗

PubMed2000

Emergency myocardial revascularization for acute myocardial infarction: survival benefits of avoiding cardiopulmonary bypass.

OBJECTIVE: Emergency coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI) is associated with increased operative mortality. It has been suggested that this mortality might be reduced by performing the operation without cardiopulmonary bypass (CPB). METHODS: Between January 1992 and April 1998, 77 patients underwent emergency CABG within 48 h of AMI. Thirty seven were operated on with CPB, and 40 without CPB. The two groups were similar regarding age, gender, left-ventricular ejection fraction (EF) and preoperative use of intra-aortic balloon pump (IABP; 50%). The mean number of grafts/patient was 3 in the CPB group, and 1.9 in the No-CPB group (P<0.0001). RESULTS: Operative mortality in the CPB group was 24% (nine of 37) compared to 5% (two of 40) without CPB (P=0.015). Follow-up ranged between 6 and 66 months. There were no late deaths in the CPB group compared to nine (22%) in the No-CPB group (P<0.0066). Patients operated on with CPB had lower rates of recurrent angina (0 versus 15%; P=0.04) and re-interventions (0 versus 15%; P=0.04). CONCLUSIONS: Our experience suggests that CABG without CPB is the preferred method of myocardial revascularization, due to the fact that it carries lower mortality than CABG with CPB. The trade-off includes increased rates of recurrent angina, re-interventions and late mortality.

Aged↗

PubMed2000

Combined repair of pectus excavatum and coronary artery bypass grafting.

Coronary artery bypass grafting (CABG) in patients with severe pectus excavatum is a surgical challenge. A two-stage correction of sternal deformities and cardiac lesions has been described and myocardial revascularization through a left lateral thoracotomy is a valid alternative in urgent situations. We report a one-stage repair of severe pectus excavatum and CABG with the use of bilateral internal thoracic arteries in a young patient requiring urgent myocardial revascularization. The technical aspects and operative consideration are discussed.

Coronary Artery Bypass↗

PubMed2000

Bilateral skeletonized internal thoracic artery grafting in 303 patients seventy years and older.

OBJECTIVES: Higher patency rates of the internal thoracic artery have led myocardial revascularization with bilateral internal thoracic arteries to be a procedure designated primarily for young patients. Fewer leg wound complications and sternal collateral flow preservation with the skeletonizing dissection technique can make bilateral internal thoracic artery grafting attractive also for elderly patients. METHODS: Between May 1996 and May 1998, 303 consecutive patients aged 70 years or older (mean age 75.5 years; range 70-92 years) underwent coronary artery bypass grafting with double skeletonized internal thoracic arteries. Forty-four (14.5%) patients were 80 years or older, and 89 (28%) had diabetes. The mean number of grafts was 3.1 per patient (2-6). RESULTS: Operative mortality was 2.6% (n = 8): it was higher for octogenarians (6.8%) than for younger patients (1.9%) (P =.06). The only significant preoperative predictors of early mortality were complicated percutaneous transluminal coronary angioplasty (P =.03) and preoperative use of intra-aortic balloon pumping (P =.03). Six patients (2%) had sternal wound infections for which chronic lung disease (P =.02) and emergency operation (P =.006) were the only significant predictors. Twenty-two (7.2%) late deaths occurred, and 1- and 3-year survivals were 93% and 90%, respectively. The 3-year survival of patients 80 years old or older was 92%. CONCLUSIONS: Bilateral grafting of the skeletonized internal thoracic artery carries relatively low morbidity and mortality in elderly patients and can be recommended for selected patients including octogenarians.

Aged↗