Arterial end-to-side grafting in coronary artery bypass grafting: the Tector procedure.

Background. The current treatment of choice in patients with three-vessel coronary disease is coronary artery bypass grafting. The use of the left internal mammary artery in bypass grafting has shown superior long-term outcomes compared with venous grafting. In our study we assess the safety and feasibility of all-arterial coronary artery bypass graft surgery using the procedure as described by Tector et al. in 2001.Methods. Between June 2001 and February 2007, we studied 133 patients eligible for non-emergency surgical revascularisation. Primary endpoints were death or re-infarction within a 30-day period. Secondary endpoints were the need for emergency coronary surgery, angioplasty and mediastinitis. Long-term follow-up had a mean duration of 33 months postoperatively.Results. All 133 patients were successfully revascularised, 98% with the off-pump technique. In 93% of the patients (n=124) full arterial grafting was achieved using both internal mammary arteries. Thirty-day mortality was 1.5% (n=2), ten re-thoracotomies were performed, one myocardial infarction and one case of mediastinitis were reported. In the next four years six additional patients died. Most of these deaths were due to non-cardiovascular causes. Two patients required angioplasty because of distal bypass graft failure and one for new native coronary artery disease. Conclusion. All-arterial bypass grafting using both internal mammary arteries with the technique as described by Tector is safe and feasible without excess deep sternal wound infections. Late major adverse cardiac events are rare and due to distal graft dysfunction, which can be treated by percutaneous coronary intervention. (Neth Heart J 2010;18:7-11.).

The immediate and long-term effect of optimal balloon angioplasty on the absolute coronary blood flow velocity reserve. A subanalysis of the DEBATE study. Doppler Endpoints Balloon Angioplasty Trial Europe.

BACKGROUND: There are limited data regarding the immediate and long-term effect of balloon angioplasty on the coronary flow reserve evaluated in a multicentre setting. METHODS AND RESULTS: A total of 86 patients with one-vessel disease and normal left ventricular function were analysed before and after optimal balloon angioplasty (diameter stenosis <35%) and at 6-month follow-up. Coronary flow reserve was assessed with a Doppler guide wire. A low coronary flow reserve (2.5 (46% vs 23% and 36% vs 16%, respectively; P<0.05) due to a trend towards restenosis (29% vs 16%; P=0.15) or a low coronary flow reserve at follow-up due to persistent elevated baseline blood flow velocity. Patients without restenosis showed a decrease or increase of coronary flow reserve during follow-up, determined by alterations of hyperaemic blood flow velocity. CONCLUSIONS: Patients with an impaired coronary flow reserve directly after optimal balloon angioplasty showed a higher target lesion revascularization rate compared to patients with a coronary flow reserve >2.5. This patient group consists of patients prone to develop restenosis, while other patients are characterized by a persistently low coronary flow reserve, probably secondary to disturbed autoregulation and/or diffuse mild coronary atherosclerosis. Coronary flow reserve alterations in patients without restenosis were related to changes in hyperaemic blood flow velocity, suggesting that this phenomenon relates to epicardial remodelling.

Pharmacodynamics and safety of lefradafiban, an oral platelet glycoprotein IIb/IIIa receptor antagonist, in patients with stable coronary artery disease undergoing elective angioplasty.

OBJECTIVE: Lefradafiban is the orally active prodrug of fradafiban, a glycoprotein IIb/IIIa receptor antagonist. The present phase II study aimed to determine the dose of lefradafiban that provides 80% blockade of the glycoprotein IIb/IIIa receptors by fradafiban, and to study the pharmacodynamics and safety of different doses in patients with stable angina undergoing angioplasty. DESIGN: A double blind, placebo controlled, dose finding study. SETTING: Four academic and community hospitals in the Netherlands. PATIENTS: 64 patients with stable coronary artery disease undergoing elective percutaneous transluminal coronary angioplasty. INTERVENTIONS: 30 mg, 45 mg, and 60 mg of lefradafiban three times daily or placebo was given for 48 hours. MAIN OUTCOME MEASURES: The primary safety end point was the occurrence of bleeding, classified as major, minor, or insignificant according to the thrombolysis in myocardial infarction (TIMI) criteria. Efficacy indices included per cent fibrinogen receptor occupancy (FRO), ex vivo platelet aggregation, and plasma concentrations of fradafiban. RESULTS: Administration of lefradafiban 30, 45, and 60 mg three times daily resulted in a dose dependent increase in median FRO levels of 71%, 85%, and 88%, respectively. Inhibition of platelet aggregation was closely related to FRO. There were no major bleeding events. The 60 mg lefradafiban group had a high (71%) incidence of minor and insignificant bleeding. The incidence of bleeding was 44% in the 30 mg and 45 mg groups, compared with 9% in placebo patients. Puncture site bleeding was the most common event. The odds of bleeding increased by 3% for every 1% increase in FRO. CONCLUSIONS: Lefradafiban is an effective oral glycoprotein IIb/IIIa receptor blocker. The clinical effectiveness of doses up to 45 mg three times daily should be investigated.

Angiographical and Doppler flow-derived parameters for assessment of coronary lesion severity and its relation to the result of exercise electrocardiography. DEBATE study group. Doppler Endpoints Balloon Angioplasty Trial Europe.

AIMS: Evaluation of angiographical and intracoronary Doppler-derived parameters of coronary stenosis severity. METHODS AND RESULTS: A total of 225 patients with one-vessel disease were studied before PTCA and at 6 months follow-up. Exercise electrocardiography was performed to document presence (n = 157) or absence (n = 138) of an ST segment shift (> or =0.1 mV). Intracoronary blood flow velocity analysis was performed to determine the proximal/distal flow velocity ratio, the distal diastolic/systolic flow velocity ratio and coronary flow velocity reserve. Receiver operator characteristic curves were calculated to assess the predictive value of these variables compared with the exercise test. The distal coronary flow velocity reserve demonstrated the best linear correlation for both percentage diameter stenosis and minimum lumen diameter (r = 0.67 and r = 0.66; P<0.01), compared to the diastolic/systolic flow velocity ratio (r = 0.19 and r = 0.14; P<0.01) and the proximal/distal flow velocity ratio (r = 0.03 and r = 0.07; not significant). The areas under the curve were 0. 84+/-0.02; 0.82+/-0.03 and 0.83+/-0.03 for diameter stenosis, minimum lumen diameter and coronary flow velocity reserve, respectively. Logistic regression analysis revealed that the percentage diameter stenosis or minimum lumen diameter and coronary flow velocity reserve were independent predictors for the result of stress testing. CONCLUSIONS: The distal coronary flow velocity reserve is the best intracoronary Doppler parameter for evaluation of coronary narrowings. Angiographical estimates of coronary lesion severity and distal coronary flow velocity reserve are good and independent predictors for the assessment of functional severity of coronary stenosis, emphasizing the complementary role of these parameters for clinical decision making.

Silicon-carbide coated coronary stents have low platelet and leukocyte adhesion during platelet activation.

BACKGROUND: Stent thrombosis and restenosis are of great clinical significance. We constructed a closed loop in vitro heparinized whole human blood circulation model for testing hemocompatibility of coronary stents. This model allows evaluation of human blood activation by blood-stent interaction in a well-controlled setting. Until now these interactions were studied in the highly coagulable pig coronary artery model. METHODS: We evaluated activation of the coagulation system and blood components by uncoated, heparin-coated, and silicon-carbide coated tantalum stents. The effects, measured by biochemical assays, were compared with stainless-steel stents. Also the inhibitory effect on platelet activation by indomethacin equal to the oral effect of 325 mg acetylsalicylic acid daily, was measured and visualized by scanning electron microscopy. RESULTS: Both activation of the coagulation system and platelets were counteracted by indomethacin, suggesting an important role for platelets in activation of the coagulation system in this model. Despite platelet activation by all stents, the SiC-coated tantalum stent demonstrates a significantly lower GpIIIa receptor-mediated platelet adhesion at the stent surface (21.7 x 10(3) counts per second/mg stent weight) compared to all other stents (stainless-steel 54.0, heparin-coated 95.7 and uncoated 76.2 x 10(3) cps/mg). Also activated leukocytes demonstrated a significantly lower CD11b receptor-mediated adhesion at the SiC-coated stent (37.0 x 10(3) cps/mg) than at the stainless-steel stent (114.5 x 10(3) cps/mg). CONCLUSIONS: Data from this in vitro circulation study show a significantly lower platelet and leukocyte adhesion at the surface of the SiC-coated tantalum stent than at the surface of stainless-steel stents or uncoated and heparin-coated tantalum stents.

Prognostic value of intracoronary flow velocity and diameter stenosis in assessing the short- and long-term outcomes of coronary balloon angioplasty: the DEBATE Study (Doppler Endpoints Balloon Angioplasty Trial Europe).

BACKGROUND: The aim of this prospective, multicenter study was the identification of Doppler flow velocity measurements predictive of clinical outcome of patients undergoing single-vessel balloon angioplasty with no previous Q-wave myocardial infarction. METHODS AND RESULTS: In 297 patients, a Doppler guidewire was used to measure basal and maximal hyperemic flow velocities proximal and distal to the stenosis before and after angioplasty. In 225 patients with an angiographically successful percutaneous transluminal coronary angioplasty (PTCA), postprocedural distal coronary flow reserve (CFR) and percent diameter stenosis (DS%) were correlated with symptoms and/or ischemia at 1 and 6 months, with the need for target lesion revascularization, and with angiographic restenosis (defined as DS > or = 50% at follow-up). Logistic regression and receiver operator characteristic curve analyses were applied to determine the prognostic cutoff value of CFR and DS separately and in combination. Optimal cutoff criteria for predictors of these clinical events were DS, 35%; CFR, 2.5. A distal CFR after angioplasty > 2.5 with a residual DS < or = 35% identified lesions with a low incidence of recurrence of symptoms at 1 month (10% versus 19%, P=.149) and at 6 months (23% versus 47%, P=.005), a low need for reintervention (16% versus 34%, P=.024), and a low restenosis rate (16% versus 41%, P=.002) compared with patients who did not meet these criteria. CONCLUSIONS: Measurements of distal CFR after PTCA, in combination with DS%, have a predictive value, albeit modest for the short- and long-term outcomes after PTCA, and thus may be used to identify patients who will or will not benefit from additional therapy such as stent implantation.

Coronary artery angioplasty with a helical autoperfusion balloon catheter.

The initial in-hospital and long-term clinical experience with a helical autoperfusion balloon catheter in the treatment of coronary artery disease is reported. This new catheter design allows blood to flow passively around the inflated balloon through a protected helical channel molded into the balloon surface. Twelve consecutive patients underwent PTCA. Continuous ST monitoring, heart rate, average peak distal coronary blood flow velocity (APV), coronary blood flow (CBF), dP/dt and systemic and pulmonary arterial pressures were determined during PTCA. During balloon inflation there were no hemodynamic changes, TIMI flow was 1.7 +/- 0.8, and APV was 39% of baseline. Luminal diameter stenosis improved from 61 +/- 17 to 29 +/- 13% (P < 0.05) following PTCA. Mean continuous inflation duration was 385 +/- 215 sec and 6/12 patients had > or = 7.5-min inflations. There were no in-hospital adverse cardiac events. One patient developed recurrent angina during 8 mo of follow-up and underwent successful PTCA of a restenotic lesion. We conclude that human plaques can be successfully dilated with a helical balloon catheter that provides autoperfusion and the ability to perform prolonged inflations with hemodynamic stability. A comparison of this PTCA catheter with standard balloon catheters is warranted.

Comparison between positron emission tomography myocardial perfusion imaging and intracoronary Doppler flow velocity measurements at rest and during cold pressor testing in angiographically normal coronary arteries in patients with one-vessel coronary artery disease.

With use of invasive methods, coronary endothelial function is generally studied by examining the response of epicardial coronary arteries to intracoronary administered acetylcholine or to cold pressor testing. Because invasive methods have substantial inherent limitations, studies should attempt to evaluate coronary endothelial function noninvasively. This study examines a noninvasive technique for endothelium-related coronary stress testing. In myocardial regions supplied by nonstenotic coronary arteries, we compared positron emission tomography (PET) myocardial perfusion imaging with intracoronary Doppler flow velocity measurements during endothelium-related stress testing. PET perfusion was examined at rest and during cold pressor testing in 10 patients with 1-vessel coronary artery disease. In nonstenotic coronary arteries, flow velocity measurements were obtained at rest, during cold pressor testing, and during intracoronary administered acetylcholine. Perfusion and flow velocity responses and stress/rest ratios were compared between the techniques during the various circumstances. Positive correlations were found between: (1) cold pressor Doppler flow velocity responses and acetylcholine Doppler flow velocity responses (r = 0.84, SEE = 0.19, p = 0.003); (2) cold pressor PET perfusion responses and cold pressor Doppler flow velocity responses (r = 0.70, SEE = 0.17, p = 0.02); and (3) cold pressor PET perfusion responses and acetylcholine Doppler flow velocity responses (r = 0.62, SEE = 0.19, p = 0.05). These results suggest that in angiographically normal coronary arteries, both the flow velocity and the perfusion responses during cold pressor testing may be related to the response to acetylcholine.

Deep seating of six French guiding catheters for delivery of new Palmaz-Schatz stents.

The delivery of new Palmaz-Schatz stents in native coronary arteries can be facilitated by using the technique of deep seating of a 6 French guiding catheter. Two patient histories are described to illustrate this new technique.

Effectiveness of sotalol in preventing supraventricular tachyarrhythmias shortly after coronary artery bypass grafting.

To investigate the effectiveness and safety of low-dose sotalol (a class III antiarrhythmic beta-blocking agent) in the prevention of supraventricular tachyarrhythmias (SVTs) and to identify predictors for the occurrence of these arrhythmias shortly after coronary artery bypass grafting, 300 consecutive patients were randomized in a double-blind, placebo-controlled fashion. Patients with severely depressed left ventricular function or other contraindications for beta blockers were excluded. Beginning at 4 hours and up to the sixth day after surgery, 150 patients received 40 mg of sotalol every 6 hours. SVT was observed in 24 (16%) of 150 low-dose sotalol-and in 49 (33%) of 150 placebo-treated patients [p less than 0.005]. In patients receiving sotalol, atrial fibrillation was the only noted tachyarrhythmia, whereas in the placebo group, 42 (28%) patients had atrial fibrillation, 3 (2%) atrial flutter, 1 (0.7%) atrial tachycardia and 3 (2%) sinus tachycardia. Drug-related adverse effects necessitating discontinuation of the drug were noted in only 2 (1%) sotalol-treated patients and 4 (3%) placebo-treated patients (p = not significant). For both groups, univariate analysis indicated that older age, 1- or 2-vessel coronary artery disease, long bypass (greater than or equal to 150 minutes) and aorta cross-clamp time (greater than or equal to 120 minutes) were predictive variables for the occurrence of SVTs. Multivariate analysis showed that male sex (odds ratio 2.3), 1- or 2-vessel coronary artery disease (odds ratio 2.0) and older age (odds ratio 1.1) were independent risk factors for increased occurrence of postoperative SVT.(ABSTRACT TRUNCATED AT 250 WORDS)