PTCA Group Research Articles

773-2 Can Low-Temperature, High-Frequency Radio Energy PTCA Influence Restenosis?

Radio frequency (RF) PTCA has previously been used with relatively low RF energy (0.25 MHz) producing primarily heat to facilitate lesion dilitation. At this low frequency (F), the RF energy does not penetrate beyond the balloon material and therefore is converted to heat within the confines of the balloon. A new device with a high-F source (13.56 MHz) not only affects balloon temp(T), but also directs electromechanical radiation to susceptible cellular components. 16 rabbits underwent bilateral focal femoral artery injury by air desiccation, followed by an atherogenic diet (1% cholesterol, 6% peanut oil) for 28 days. Femoral artery PTCA was performed with a 2.5 mm balloon catheter, following a protocol (3 inflations, 6 atmospheres, 60 sec.) on one femoral artery, while the opposite femoral artery underwent 3 successive RF PTCA's at 13.56 MHz, restricting T to 55 C. Angiograms were performed pre-PTCA, following PTCA, and approx. 3 weeks later at the time of sacrifice. Analysis of vessel dimensions, and percent stenosis were done by independent, blinded, quantitative measurement (QCA). There were no Significant differences seen in either group with regard to normal reference vessel size, lesion MLD, or diameter stenosis. Importantly, subsequent angiographic lesion progression was significantly limited in the RF PTCA group (8% MLD reduction) vs. the PTCA group (23% MLD reduction). Preliminary results in this restenosis model are encouraging and warrant further investigation.

792-2.Is the Anti-Restenosis Effect of Stent (vs PTCA) Greater in LAD Vessels? A Subgroup Analysis of the STent REStenosis Study

In the multicenter randomized STent REStenosis Study (STRESS), stent (S) implantation has shown to reduce restenosis (RES) by 26% compared with PTCA. To determine the impact of Svs PTCA in reducing RES in various vessel locations, we analyzed the data from STRESS in LAD and non-LAD vessels. LAD PTCA N = 98 LAD S N = 96 Non-LAD PTCA N = 104 Non-LAD S N = 109 Final % stenosis 34 ± 15 17 ± 11 † 35 ± 14 20 ± 12 † Acute gain (mm) 1.14 ± 0.47 1.62 ± 0.43 † 1.32 ± 0.49 1.81 ± 0.47 † Late Loss (mm) 0.52 ± 0.55 0.78 ± 0.57 * 0.34 ± 0.57 0.73 ± 0.57 † Net gain (mm) 0.59 ± 0.55 0.88 ± 0.62 * 1.03 ± 0.61 1.06 ± 0.61 RES (>50% stenosIs) 52.6 32.9 * 29.9 29.5 * . p ≤ 0.01 † . p ≤ 0.0001 compared S with PTCA In both LAD and non-LAD vessels, S (compared with PTCA) achieved a greater acute ga in and resulted in a lower final % stenosis. Late loss was also greater in S than PTCA group and similar for LAD and non-LAD vessels. However, in PTCA pts, late loss was much lower in non-LAD vessels (vs LAD). Thus, the overall net gain and RES in non-LAD vessels were similar for S.and PTCA, whereas the net gain was greater after S in LAD vessels and resulted in much lower RES compared with PTCA. Similarly, the difference in eventfree survival (freedom from death, MI, CABG, or repeat PTCA) between S and PTCA was greater in LAD (77% vs 66%, P = 0.06) than non-LAD vessels (78% vs 72%, NS). STRESS substudy analysis indicates 1) S provides uniformly greater improvement of angiographic results in all lesion locations compared with PTCA, 2) much greater anti-restenosis and clinical benefits in S pts within the LAD vessels, and 3) more aggressive post-S dilatation strategies (to further reduce final % stenosis) are recommended for non-LAD vessels to achieve greater differential anti-restenosis benefit for S.

710-2 Coronary Stents Versus Balloon Angioplasty for Aorto-Coronary Saphenous Vein Bypass Graft Disease: Interim Results of a Randomized Trial

The purpose of this interim analysis of the SAVED Restenosis Trial was to assess the acute results of balloon angioplasty (PTCA) and elective PalmazSchatz coronary stent placement in the treatment of de novo venous bypass graft lesions. As of August 1, 1994, 128 patients (60 PTCA, 68 Stent) have been enrolled at 13 centers. Baseline demographics were similar in both groups. Mean graft ages in the PTCA and Stent groups were 9.8 ± 4.2 vs 9.7 ± 4.5 years (p = ns). Initial angiographic results by core laboratory analysis and clinical events from 0 to 30 days were as follows: Angiographic results PICA Stent Clinical Events (%) PICA Stent Vessel diameter (mm) 3.21 3.18 Death 3.3 5.9 Baseline mid (mm) 0.98 0.93 O-wave MI 1.7 1.5 Final mid (mm) 2.12 2.85 Bypass Surgery 6.7 0 ** Final % diam stenosis 33 12 * Closure: ≥24 hrs 33 2.9 Procedure success (%) 85 96 ** >24 hrs 1.7 0 * p < 0.01 ** p < 0.05 vs PICA One or more major clinical events occurred in 11.7% of PTCA patients vs 5.9% of Stent patients (p = ns). Crossover from assigned to alternative therapy (including bypass surgery) was 13.3% for the PTCA group vs 1.5% for the Stent group (p < 0.01). In conclusion, the preliminary findings of this prospective trial indicate: (1) Elective stent placement in de novo saphenous vein bypass graft lesions achieves a superior initial angiographic result compared to balloon angioplasty; (2) Stents confer a salutary effect on early clinical events with less frequent need for alterna1e therapies including coronary bypass surgery.

902-1 Mechanisms of Acute Luminal Enlargement in PTCA and Stent: A Prospective Intravascular Ultrasound Study

Because intravascular ultrasound (IVUS) enables quantitative analysis of vessel size, plaque burden, and luminal dimensions, it is uniquely suited to determine the in vivo mechanisms of acute gain following coronary intervention. The purpose of this study was to compare the mechanisms of acute luminal enlargement in a patient population randomized to PTCA or stent. Between 11/93 and 7/94, 23 patients (PTCA = 11, Stent = 12) underwent prospective pre-intervention (Pre) and post-procedure (Post) IVUS imaging using a 2.9 Fr. 30 MHz monorail catheter (CVIS). Pre and Post minimal lumen area (MLA), minimal external elastic lamina area (EELA), and plaque&media area (P&MA) were determined. There was no significant statistical difference in these values pre-intervention. Acute gain (ΔMLA), vessel expansion (ΔEELA) and plaque compression (ΔP&MA) were then calculated. All calculated areas are in mm 2 and are summarized below: PTCA (n = 11) Stent (n = 12) p-value Acute Gain (ΔMLA) 4.0 ± 0.63 6.66 ± 0.36 0.001 Plaque Compression (ΔP&MA) 3.29 ± 0.73 3.82 ± 0.70 NS Vessel Expansion (ΔEELA) 0.76 ± 0.49 2.65 ± 0.68 0.036 1) Intracoronary stenting is associated with a significantly larger acute luminal gain. 2) This acute gain is due to a greater increase in EEL dimensions in the stent group and is suggestive of greater vessel expansion, less recoil, or both. 3) In the PTCA group, vessel expansion accounts for only 20% of the acute gain, while plaque compression appears to be the predominant mechanism of luminal enlargement.

1018-49 Assessing a Strategy of Stand-alone Extraction Atherectomy Followed by Staged Stent Placement in Degenerated Saphenous Vein Graft Lesions

Previously, we reported the high incidence of ischemic complications due to distal embolization (DE) following extraction atherectomy (TEC) of degenerated saphenous vein grafts (DSVG: grafts with lumen ectasia or irregularities comprising ≥50% of the graft length), frequently caused by adjunct PTCA (Group I). To assess whether a staged strategy (initial stand-alone TEC ± lyric therapy, followed by coumadin and stenting 1–2 months later) could reduce ischemic complications, we performed a pilot study in 28 pts with DSVG (Group II). Demographics and graft age (100 ± 47 vs. 99 ± 42 months) were similar, except for more recent MI in Group II (58.3% vs. 22.7%, P = 0.03). Group I (n = 44) Group II (n = 28) % DS (Pre/Final) 79 ± 14/30 ± 24 * 80 ± 17/45 ± 19 DE (%) 22.7 ** 10.7 Any In-hospital Complications 11.4% *** 0% Death/CABG/MI (%) 6.8/2.3/4.5 0/0/0 DS = diameter stenosis * p < 0.001 ** p = 0.20 *** p = 0.15 vs. Group II Among 27 pts in Group II eligible for follow-up (> 1 month), there were no major ischemic complications. There were 4 total occlusions [1 non-Q wave MI at 4 months and 3 silent occlusions at 6 weeks (1) and 2 months (2)]. 9 without clinical indication for additional therapy, 11 staged procedures with stenting (follow-up % DS = 56 ± 30%), and 3 without significant stenosis on follow-up angiography. We conclude that this staged angioplasty strategy in degenerated saphenous vein graft lesions: 1) may reduce distal embolization, but most importantly , avoids major in-hospital ischemic complications during the initial procedure: but 2) at the expense of ≈15% graft occlusions, which occurred more than 6 weeks after the initial procedure: and 3) prevented any deaths either during the initial procedure or during the follow-up period. These results underscore the importance of early (1 month) follow-up in all patients undergoing this staged TEC, followed by stent procedure in treating complex degenerated saphenous vein graft lesions.

Comparison of primary angioplasty versus thrombolytic therapy for acute myocardial infarction

To determine the relative merits of primary percutaneous transluminal coronary angioplasty (PICA) and intravenous thrombolytic therapy for acute myocardial infarction, 12 tertiary care hospitals entered patients who had ≥30 minutes of chest pain and were admitted to a cardiac intensive care unit within 12 hours of symptom onset into a prospective registry. Of 1,170 such patients, 118 (10%) underwent primary PTCA and 230 (19%) received intravenous thrombolytic therapy within 6 hours of registry hospital admission (144 at the registry hospital and 86 prior to arrival at the registry hospital). Baseline demographic characteristics of PTCA and thrombolytic subgroups were remarkably similar. The interval from initial evaluation at the registry hospital to treatment was shorter with intravenous thrombolytic therapy than with primary PTCA (64 vs 104 minutes, p < 0.001), as was the interval from pain onset to treatment (184 vs 252 minutes, p < 0.001). Among the 230 thrombolytic patients, coronary arteriography and PTCA were performed within the first 24 hours in 44% and 18%, respectively, and during the entire hospitalization in 90% and 49%, respectively. During hospitalization, blood was transfused in 16% of the 230 thrombolytic patients versus 5.9% of the 118 PTCA patients (p < 0.001). Otherwise, adverse events during the initial hospitalization were similar in PTCA and thrombolytic groups. Survival at 1-year follow-up was 88% in the PTCA group and 91% in the thrombolytic group (p = NS), and survival free of reinfarction was 85% and 88%, respectively (p = NS). Multivariable analysis, adjusting for baseline characteristics, found no evidence that use of PTCA rather than thrombolytic therapy significantly impacted survival or survival free of reinfarction at 1 year. These observational registry data suggest that patients undergoing primary PTCA for acute myocardial infarction have similar demographic characteristics and similar outcome as patients receiving intravenous thrombolytic therapy.

PTCA再狭窄, その予防と対策

We made a preliminary study on the possibility of reducing restenosis after PTCA by administering lipid lowering therapy prior to PTCA. The 73 cases studied included 18 cases who received Probucol 750 mg/day for more than 2 weeks (Group P-1), 17 cases who received Pravastatin 10 mg/day for more than 2 weeks (Group M-1), 23 cases who received Probucol 750 mg/day for less than 2 weeks (Group M-2), and 15 cases who re ceived Pravastatin 10 mg/day for less than 2 weeks (Group M-2). We also treated 9 cases who have a serum cholesterol level of 230 mg/dl or more despite taking Probucol by LDL-apheresis 3 times prior to and after PTCA (Group A).PTCA was indicated in cases with 90% or more coronary stenosis according to the AHA severity classification: We regarded cases with less than 50% lesion stenosis as successful PTCA, and cases with 75% or more lesion stenosis at CAG examination 5 months later as restenosis.There were no significant differences in these 5 groups in the target vessel to be dilated, number of target vessels, severity of stenosis before PTCA, residual stenosis after PTCA, and coronary risk factors such as age, hypertension, diabetes, and smoking.The rate of restenosis after PTCA showed 2 of 18 cases (11.1%) in group P-1, 5 of 17 cases (29%) in group M-1, 9 of 23 cases (39.1%) in group P-2, 1 of 15 cases (7%) in group M-2, and 1 of 9 cases (11%) in group A. In contrast to failure reducing restenosis rate in group M-1, lipid parameters such as total cholesterol, LDL-cholesterol, apoprotein B, ratio of apoprotein B to apoprotein AI, Atherogenic Index (LDL/HDL) had been much more improved in this group than group P-1. However, serum Lp(a) level of group M-1 showed 27.2 mg/dl which was significantly elevated than those of group P-1 and group M-2, where it showed 13.8 mg/dl and 17.1 mg/dl respectively.In Group A serum cholesterol level showed 359 mg/dl at first, 274 mg/dl after diet control and taking probucol, and came to be 161 mg/dl after LDL-apheresis which could to be thought almost equal to the level at the time of PTCA.Then we can conclude that (1) combined lipid lowering therapy by Probucol and LDL-apheresis may contribute to reducing the restenosis rate after PTCA. (2) To reducing the restenosis rate after PTCA we had better consider to choose lipid lowering drug which acts not only to lower serum lipid level but also to improve interrelation to endothelium and intimal cells of coronary artery. (3) In cases of restenosis who got lowered serum cholesterol level at the time of PTCA they may have elevated serum Lp(a) level.

Percutaneous transluminal Coronary Angioplasty and coronary artery bypass surgery. Early and follow-up clinical results.

To evaluate the efficacies of percutaneous transluminal angioplasty (PTCA) and coronary artery bypass grafting (CABG) for angina pectoris, early and follow-up data were reviewed in 495 patients who had undergone these procedures from 1986 to 1988. In 173 patients with single vessel disease, there were no significant differences in initial success rate and early and late incidences of major complications or cardiac death between 152 patients with elective PTCA and 21 with urgent. When compared in 161 patients with multivessel disease, however, significant differences in success rate were found between 130 patients in the elective PTCA group and 31 in whom PTCA was urgent (81.6% vs. 64.5%, p less than 0.05). Significant differences were also found in early incidence of major complications (3.1% vs. 12.9%, p less than 0.01), early mortality (1.5% vs. 9.7%, p less than 0.01), and the late incidence of cardiac events (6.2% vs. 25.0%, p less than 0.01). These results show that freedom from cardiac death and overall cardiac events in the elective PTCA group as significantly better than that in the urgent group at 42 months of follow-up. Comparing early and follow-up results, on the other hand, there was no statistically significant difference between the elective and urgent CABG groups. Thus, there appear to be limitations on the urgent use of PTCA for refractory unstable angina caused by multivessel disease, and urgent CABG was recommended to high-risk patients of urgent PTCA.

Functional status after coronary artery bypass grafting and percutaneous transluminal coronary angioplasty

Two cohorts of consecutive patients of comparable age with similar preprocedure cardiac function who underwent either coronary artery bypass grafting (CABG; n = 106) or percutaneous transluminal coronary angioplasty (PTCA; n = 64) were entered into a prospective comparison study examining functional status and return to work during the first year of recovery. Patients were evaluated using standardized functional status instruments for activities of daily living, work performance, social activity, mental health and quality of social interaction at 1, 6 and 12 months after the procedure. Within the CABG group, statistically significant improvements of functional status on every subscale were noted over the 1-year follow-up. Patients undergoing PTCA demonstrated significant improvement in all dimensions except for the quality of interaction at 1 year as compared with baseline. When the 2 groups were compared, the PTCA group demonstrated greater participation than the CABG group in routine daily physical and social activities at 1 and 6 months, but this apparent advantage disappeared by 1 year. Measures of psychological functioning were better after CABG than after PTCA. A reduction in the number of those with employment occurred in both the CABG and PTCA groups, independent of physical functional status measures, which improved in both groups after the procedures. For those with employment, the CABG group reported the greatest improvement in work performance.

Relative cost of coronary angioplasty and bypass surgery in a one-vessel disease model

A national study was carried out to determine the relative costs of PTCA and CABG. Baseline clinical criteria for the 2 groups were similar. Data were collected in 186 sets for the PTCA group and 175 sets for the CABG group. Male patients make up 81% of the PTCA group and 80% of the CABG group. Mean hospital stay was 12 ± 5 days in the CABG group, compared with 4 ± 2 days in the PTCA group (p < 0.001). The base charges for hospital and professional components of the CABG procedure were $15,580 ± $2,159, whereas the same charges for the PTCA procedure were $5,315 ± $2,159 (p < 0.001). With an 80% primary success rate, which was the group mean success rate, the average dollar savings per PTCA procedure would be $7,149, or $7,149,000 per 1,000 cases. Thus, PTCA for revascularization in 1-vessel CAD is significantly more cost-effective than CABG in the short term.

Role of percutaneous transluminal coronary angioplasty in the treatment of unstable angina: Report from the national heart, lung, and blood institute percutaneous transluminal coronary angioplasty and coronary artery surgery study registries

The acute and long-term consequences of PTCA performed in patients with unstable angina was determined in 442 patients with 1-vessel CAD who were enrolled in the NHLBI PTCA Registry. These patients were compared with 214 similar patients in the PTCA Registry with stable angina and with 330 patients with unstable angina from the NHLBI CASS Registry who underwent CABG. The 3 groups had similar baseline characteristics. The immediate angiographic success after PTCA was not different between patients with stable and those with unstable angina. The in-hospital mortality rate was 0.9 % for the PTCA group with unstable angina and 0.47% for the PTCA group with stable angina. The combined 18-month mortality and MI rate was low in both groups (10.8 and 9.5%, respectively). No differences were observed in the mortality and MI rates between patients with unstable angina treated surgically or with PTCA. Both revascularization procedures markedly reduced symptoms of angina. Ninety-two percent of the PTCA group reported improvement in their angina, whereas 80 % of the surgical group had a reduction in angina (p < 0.05). The results from this observational study suggest that PTCA can be performed as safely and successfully in patients with unstable angina as in those with stable angina. PTCA compares favorably with CABG in patients with unstable angina in that the procedure is associated with low mortality and morbidity rates, while marked improvement in symptoms can be expected. Thus, PTCA could be considered an alternative to CABG in patients with unstable angina who have the appropriate anatomic characteristics.

Immediate Clinical Outcome of 600 Cases of Percutaneous Coronary Intervention (PCI)

This is an ongoing study done in National Institute of Cardiovascular Diseases (NICVD) during the period April 2002 to October 2007, few cases were done in Eurobangla Heart Hospital, Lab Aid Cardiac Hospital &amp; National Heart Foundation, SSMC &amp; MH, Metropolitan Medical Center. Total number of study population was 600 with male 550 &amp; female 50. Indication of Percutaneous coronary intervention (PCI) was- Unstable angina (with no prior myocardial infarction) 240 cases, MI inferior (with post Myocardial infarction angina) 204 cases &amp; MI anterior (with post MI angina) 156 cases. The risk factors were Hypertension (HTN) 310 cases (52%), smoking 426 cases (71%), Diabetes Mellitus (DM) 180 cases (30%), Positive family history for ischemic heart diseases (IHD) 120 cases (20%), Hyperlipidemia 150 cases (25%). Total number of target coronary arteries was 760 and total number of lesion was 803 of which780 lesions treated. Distribution of 803 lesions were left anterior descending coronary artery (LAD) 389 (proximal LAD 152, mid LAD 177, distal LAD 60), Right coronary artery (RCA) 230 (proximal 94, mid RCA 93, Distal RCA 26, RCA PD 17), Left circumflex coronary artery (LCX) 137 (proximal LCX 60, mid LCX 54, distal LCX 16, LCX PD 07), diagonal 15, obtuse marginal (OM) 20, ramus intermedius. Angiographic diagnosis of the patients were Single vessel disease 312 (52%), Double vessel disease 156 (26%) &amp; Triple vessel disease 132 (22%). Number of lesions treated were 803 of which 780 lesions was treated. PTCA with stenting done in 725 lesion &amp; 34 lesions treated with plain PTCA. Total occlusion was treated in 85 cases. The native vessel has a mean reference diameter was 3.03 ± 0.61 mm. Residual stenosis after deploying stents was &lt;10%. Our success rate was-angiographic success 96%, procedural success 94% &amp; clinical success 92%. Total mortality was 03. One patient having triple vessel disease died on P the procedure due to sudden cardiac arrest due to asystole, one pt died on the table due to acute closure by thrombus &amp; one patient died on 4th day due to huge retroperitoneal hemorrhage &amp; shock. Sub acute stent thrombosis occurs in 3 cases causing acute myocardial infarction &amp; one case required emergency CABG. Following procedure, in hospital course of the patients were uneventful. All the patients were discharged by three to fourth day of the procedure with improvement of their clinical condition. So the result of our study is good both in plain PTCA group &amp; PTCA + stent group. &#x0D; &#x0D; (University Heart Journal 2007; 3 : 50-56)