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Between January 2003 and September 2006, a total of 2,541 patients had percutaneous coronary intervention (PCI). Of these, 202 (226 grafts) had at least one saphenous vein graft (SVG) intervention. Adjunctive distal embolic protection (DEP) devices were attempted in 123 SVGs (54.4%). The 30-day major adverse cardiac event (occurrence of death, myocardial infarction, or target vessel revascularization) rate in the overall group was 11.9%. The presence of angiographic thrombus independently predicted DEP use while the presence of in-stent restenosis predicted no DEP use. Although the presence of all angiographic technical feasibility criteria independently predicted DEP use, only 72 (32.4%) and 33 (14.6%) of the SVGs would have been eligible for the occlusive balloon- and filter-based distal embolic criteria, respectively. The most common technical reason for ineligibility was a graft size smaller than 3.0 mm, followed by the lack of a long enough landing zone. In a subset of 21 (9.3%) completely occluded lesions which would have excluded DEP use, angiographic success was 66.7%, and that was predicated on successful debulking with rheolytic thrombectomy in 13 (61.9%) with subsequent DEP in 5 (23.8%). In conclusion, not all grafts can be protected, and even in those that can, such protection may be incomplete. Newer embolic protection devices, such as the Proxis((R)), were recently introduced to expand the applicability to a wider population of vein grafts. However, further design improvements such as device miniaturizations applicable to sub-3.0-mm vessels and better particle removing/filtering mechanisms are needed in order to expand the use of embolic protection to reduce the persistently high complication rates associated with this difficult- to-treat subset of patients.

UNLABELLED To assess whether differences in design (geometry, flexibility) and material (electrostatic behavior) may influence the acute and late outcome following intracoronary stent implantation in the treatment of acute or threatened closure after prolonged balloon inflations, 50 patients were randomized to receive either a Palmaz-Schatz stent (n = 25) or a Strecker stent (n = 25). RESULTS [table: see text] CONCLUSION Both Palmaz-Schatz and Strecker stents are equally effective in restoring vessel patency in bail-out situations. The incidence of complications is high and similar for both stents if they were used after failed prolonged balloon inflations. Differences in design and material do not seem to influence the results.

To examine the direct effects of nitroglycerin (NTG) on anterior regional coronary blood flow, electrocardiographic and hemodynamic responses were measured immediately before, during, and after brief coronary occlusion in 17 patients undergoing left anterior descending coronary angioplasty (PTCA). Hemodynamic data and the time from the onset of coronary occlusion to 1.0 mm ST elevation or depression were compared for matched control and NTG occlusion periods. Ten seconds before the “NTG” occlusion, 200 μg of NTG was injected into the left coronary artery. Baseline and occlusion level great cardiac vein flow (thermodilution) was similar for both occlusion periods (93 ± 27 to 59 ± 23 mL/min for control; 95 ± 27 to 56 ± 22 mL/min for NTG occlusion). NTG reduced mean arterial pressure (91 ± 11 to 82 ± 15 mmHg, P < 0.05) during increased basal great vein flow (95 ± 27 to 127 ± 54 mL/min p < 0.01) immediately prior to occlusion. Great vein hyperemic flow after release of occlusion increased 21 ± 30% versus 36 ± 40% (P = ns) after control occlusion. There were no differences in heart rate or systolic-heart rate pressure products, time to ischemic ST-T wave changes or the maximal hyperemic responses from the control occlusion. These data suggest that during the initial minutes of coronary occlusion, the marked but transient coronary vasodilation induced by intracoronary NTG does not significantly modulate myocardial ischemia or regional coronary blood flow responses. The clinical benefits of NTG during PTCA most likely occur more through other mechanisms than direct myocardial flow augmentation. (J Interven Cardiol: 1988:1:1)

The use of continuously monitored pulmonary artery oxygen saturation (PAOS)for the assessment of transient myocardial ischemia was examined in a controlled human model during coronary angioplasty, producing brief reversible episodes of myocardial ischemia. Clinical and anatomic variables were prospectively recorded and correlated with changes in continuous PAOS during repeated episodes of coronary artery occulsion. Forty-seven patients underwent left anterior descending (LAD, n = 43) or circumflex (n = 4) coronary balloon occlusion. Patients were subgrouped by PAOS responses: group 1, 22 patients with ± 10% drop in PAOS during balloon inflation and group 2, 25 patients in whom the PAOS signal was stable or only minimally affected during transient ischemia. Anatomical features analyzed included normal coronary diameter, location of lesion (e.g., proximal to the first septal branch) and extent of myocardium supplied by an occluded artery (LAD extending beyond the apex of the left ventricle [LV] or a large diagonal after the occlusion point). Left ventricular wall motion abnormalities, presence of other coronary artery disease, diabetes and hypertension were also analyzed. Groups were similar with respect to age (61 ± 13, 62 ± 10 years), LV ejection fraction, LV score, incidence of hypertension and diabetes or anatomic scores (2.2 ± 1.0, for group 1 vs 2.0 ± 0.9 for group 2), normal angiographic arterial diameter and presence of coronary collateral supply. Although some episodes of myocardial ischemia in electively studied stable patients may be associated with significant reducitons in PAOS, the occurrence or degree of PAOS reduction is not predicted by coronary anatomy, LV function or other clinical variables. Use of PAOS to identify ischemic events in more critically ill patients is potentially useful, but must be assessed individually during the clinical situation. (J Interven Cardiol 1988:1:2)

Percutaneous transluminal coronary angioplasty (PTCA) may improve coronary vasomotor responses after relief of flow limiting luminal narrowings. To evaluate the effects of PTCA on nitro-glycerin-induced augmentation of coronary blood flow, great cardiac vein (thermodilution) blood flow and systemic hemodynamic responses to low (50 meg) and high (200 meg) dose intracoronary nitroglycerin (NTG) before and after PTCA were measured in 20 patients undergoing left anterior descending artery (LAD) balloon dilatation. Before PTCA, low dose NTG increased great vein flow 44 ±31% (from 56 ± 21 to 81 ± 33 mL/min, P < 0.01). High dose NTG increased great vein flow 55 + 30% (56 ± 23 to 87 ± 38 mL/min, P < 0.01). PTCA reduced LAD stenosis (79 ± 13 to 20 ± 9%, P < 0.01) and translesional pressure gradient (49 ± 10 to 15 ± 13 mmHg, P < 0.01) increasing post-PTCA basal great vein flow 45% (56 ± 21 mL/min to 81 ±27 mL/min, P < 0.01). After PTCA, low dose NTG increased great vein flow only 26 ± 23% (81 ± 27 to 101 ± 39mL/min, P < 0.01; P < 0.05 versus 44 ± 31% before PTCA). The high dose NTG-induced coronary hy-peremic responses were unchanged after PTCA (55 ± 30, 55 ± 34%, P = ns). When compared to dose related NTG hyperemic responses in 10 patients with normal LAD, the post-PTCA responses remained attenuated. These data indicate that NTG-induced augmentation of coronary blood flow remains unchanged or attenuated and does not appear to be improved by PTCA. These findings should be considered when evaluating pharmacological coronary blood flow responses after PTCA. These data also suggest that epicardial coronary resistance plays a limited role in NTG-induced augmentation of coronary blood flow inpatients with atherosclerotic coronary disease. (J Interven Cardiol 1988:1:2)