Dejan Orlic

MODIFIED T-STENTING TECHNIQUE WITH CRUSHING FOR BIFURCATION LESIONS: IMMEDIATE RESULTS AND 30-DAY OUTCOME

We report a new stenting technique employed in 20 consecutive patients to treat true bifurcation lesions using the Cypher stent (Cordis, Warren, NJ). Both stents are advanced at the site of the bifurcation. The proximal marker of the side‐branch stent must be situated in the main branch at a distance of 4–5 mm proximal to the carina of the bifurcation and the main branch stent must cover the bifurcation as well as the protruding segment of the side‐branch stent. The side‐branch stent is deployed first and balloon and wire are removed. The stent deployed in the main branch completely covers and crushes the protruding segment of the side branch stent against the vessel wall of the main branch. Following main‐ and side‐branch predilatation, stents were successfully deployed in all lesions. Final kissing balloon inflation was performed in seven patients. Two patients had in‐hospital myocardial infarction and one patient underwent in‐hospital re‐PTCA due to a dissection distal to a stent. No other major adverse cardiac events were observed in‐hospital and during 1‐month clinical follow‐up. Treatment of bifurcation lesions using crushing stent technique is feasible with acceptable rate of procedural complications. Angiographic follow‐up is necessary to prove the advantage of this specific technique to give complete coverage of the ostium of the side branch with a drug‐eluting stent. Catheter Cardiovasc Interv 2003;60:145–151.

Preliminary Observations Regarding Angiographic Pattern of Restenosis After Rapamycin-Eluting Stent Implantation

Background—Restenosis after implantation of drug-eluting stents (DES) is a rare phenomenon, occurring more frequently peri-stent. Methods and Results—We evaluated the pattern of restenosis occurring after implantation of DES in unselected lesions. From April 15 to December 6, 2002, we treated 368 patients with 735 lesions by using 841 rapamycin-eluting stents (Cypher, Cordis, a Johnson & Johnson Company). Mean baseline lesion length was 17.48±12.19 mm, and mean stent length was 27.59±14.02 mm. Follow-up ischemia-driven angiography was performed in 24 patients. Eleven patients had angiographic restenosis (≥50% diameter stenosis) in 14 stented segments (stent and 5 mm proximal and distal to the stent). The pattern of restenosis in all 14 stented segments was focal, and in 6 of them it was multifocal, occurring inside the stents. Mean length of restenotic lesions was 5.62±1.90 mm, with a range from 2.54 to 8.44 mm. One multifocal restenosis involved also the distal stent margin. Intravascular ultrasound evaluation at follow-up, performed in 2 patients, showed significant lumen obstruction attributable to in-stent hyperplasia in both cases. Individual cases can be viewed in the Data Supplement. Conclusions—The pattern of restenotic lesions after rapamycin-eluting stent implantation was focal and mostly inside the stent.

Differential Effects of Drug-Eluting Stents on Local Endothelium-Dependent Coronary Vasomotion

OBJECTIVES The aim of our study was to compare coronary vasomotion after implantation of a second-generation biolimus A9-eluting stent (BES) and of a sirolimus-eluting stent (SES). BACKGROUND Drug-eluting stents (DES) have been associated with impaired local coronary vasomotion, delayed endothelialization, and increased late thrombotic risk. New DES with different drugs, pharmacokinetics, and polymers have been developed. METHODS Nineteen patients with a BES and 15 patients with a SES were studied 9 months after stent implantation. Endothelium-dependent and -independent coronary vasomotion were tested proximally and distally to the stent as well as at a reference segment during right atrial pacing at increasing heart rates. Quantitative coronary angiographic measurements were performed offline. RESULTS Of the patients with BES, 2 showed vasoconstriction with increased heart rate and 17 showed vasodilatation. Of the patients with a SES, 9 showed vasoconstriction while 6 showed vasodilatation. The SES showed significant vasoconstriction at both the proximal (-2.3 +/- 10% vs. 7.9 +/- 10%) and the distal (-5.4 +/- 9% vs. 6.1 +/- 8%) segments to the stent compared with the BES (p = 0.003 for proximal, p < 0.001 for distal segment). Endothelium-independent vasomotion after intracoronary nitrates did not differ significantly between the 2 groups (p = NS for proximal and distal segment). CONCLUSIONS Unlike the case with the SES, endothelium-dependent vasomotion at adjacent stent segments seems to be preserved after BES implantation. This result may be explained by the different drug release kinetics, DES design, or characteristics of polymer used in the stent system.

Intraprocedural Stent Thrombosis During Implantation of Sirolimus-Eluting Stents

Background—Intraprocedural stent thrombosis (IPST) is a rare event (<0.01% in our experience with bare metal stents), with the exception of specific settings such as acute myocardial infarction, thrombus-containing lesions, and dissections. We report the occurrence of this event during elective implantation of sirolimus-eluting stents. Methods and Results—Between April 2002 and August 2003, 670 patients with 1362 lesions were treated with Cypher (Cordis, Johnson and Johnson Co) sirolimus-eluting stent implantation in San Raffaele Hospital and EMO Centro Cuore Columbus. Diabetes mellitus was present in 142 patients (21%), and 164 (24.5%) had unstable angina. Pretreatment with glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors was carried out in 235 patients (35%). Total stent length per vessel was 42.9±28.3 mm. IPST occurred in 5 patients (0.7%). None of the patients with IPST were pretreated with GP IIb/IIIa inhibitors. Using univariate exact logistic regression, only total stent length per vessel, in millimeters (exact OR, 1.03; 95% CI, 1.011 to 1.046; P = 0.0028), was associated with the occurrence of IPST. Conclusions—Stent length was associated with the occurrence of IPST. Particular attention will need to be directed to this potential complication when long sirolimus-eluting stents are being used.

Outcome Comparison of 600- and 300-mg Loading Doses of Clopidogrel in Patients Undergoing Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction Results From the ARMYDA-6 MI (Antiplatelet therapy for Reduction of MYocardial Damage during Angioplasty-Myocardial Infarction) Randomized Study

OBJECTIVES The purpose of this study was to compare 600- and 300-mg clopidogrel loading doses in patients with ST-segment elevation myocardial infarction (STEMI). BACKGROUND Given the high thrombotic risk of patients with STEMI, greater platelet inhibition may improve outcome in those patients receiving percutaneous coronary intervention (PCI). Although observational data suggest that pretreatment with a 600-mg clopidogrel loading dose may be more effective than the 300-mg regimen in primary PCI, this hypothesis has never been tested in a randomized study. METHODS A total of 201 patients undergoing primary PCI for STEMI randomly received a 600-mg (n = 103) or 300-mg (n = 98) clopidogrel loading dose before the procedure. The primary endpoint was the evaluation of the infarct size, defined as the area under the curve of cardiac markers. RESULTS Infarct size was significantly lower in the high-dose regimen: median creatine kinase-myocardial band 2,070 ng/ml (interquartile range [IQR]: 815 to 2,847 ng/ml) versus 3,049 ng/ml (IQR: 1,050 to 7,031 ng/ml) in the 300-mg group, p = 0.0001; troponin-I 255 ng/ml (IQR: 130 to 461 ng/ml) versus 380 ng/ml (IQR: 134 to 1,406 ng/ml), p < 0.0001. In the 600-mg arm, Thrombolysis In Myocardial Infarction flow grade <3 after PCI was less frequent (5.8% vs. 16.3%, p = 0.031), left ventricular ejection fraction at discharge was improved (52.1 ± 9.5% vs. 48.8 ± 11.3%, p = 0.026), 30-day major adverse cardiovascular events were fewer (5.8% vs. 15%, p = 0.049), and bleeding/entry site complications were not increased (secondary endpoints). CONCLUSIONS In STEMI patients, pre-treatment with a 600-mg clopidogrel loading dose before primary PCI was associated with a reduction of the infarct size compared with a 300-mg loading dose, as well as with improvement of angiographic results, residual cardiac function, and 30-day major adverse cardiovascular events; further studies are warranted to evaluate impact of such strategy on survival.

Preliminary experience with the frontrunner coronary catheter: Novel device dedicated to mechanical revascularization of chronic total occlusions

The novel device Frontrunner coronary catheter (FCC), dedicated to recanalization of chronic total occlusions (CTOs), relies on blunt microdissections inside the plaque, allowing passage of guidewire through the lesion and adjunctive angioplasty. In order to evaluate efficacy and safety of recanalization using the FCC device, we included patients with de novo or restenotic CTOs in a native coronary artery with prior failure using a guidewire or considered unsuitable for guidewire attempt in which the FCC was attempted first. Between October 2000 and June 2003, 50 patients with 50 CTOs were included in the study. Thirty‐two patients had prior failure with a mechanical wire. Device and angiographic success were obtained in 25 (50%) occlusions: 53% in lesions with prior guidewire failure and 44% when FCCs were attempted first (P = 0.8). During the first year of experience, angiographic success was 42% (5 occlusions) and in the third year 75% (12 occlusions; P = 0.12). Coronary perforation occurred in nine (18.0%) patients, leading to tamponade in two (4%) patients. Perforations occurred in 5 out of 12 attempted patients during the first year and in 4 out of 38 patients in the following period (41.7% vs. 10.5%; P = 0.04). Serious adverse events occurred in five (10%) patients within 30‐day follow‐up. Four non‐Q‐wave myocardial infarctions occurred in hospital (clinical success 42%) and one death 7 days after the index procedure. The use of FCC increases the success to open chronic total occlusions refractory to mechanical guidewires or that were considered unsuitable for an attempt with a guidewire. The risk of coronary perforation due to FCC use is relatively high and it can decrease with experience. Catheter Cardiovasc Interv 2005;64:146–152.

The Pharmacokinetics of Biolimus A9 after Elution from the Nobori Stent in Patients with Coronary Artery Disease: The NOBORI PK Study

The aim of this study was to assess the pharmacokinetics and tolerability of Biolimus A9 eluted from Nobori coronary stents.

The value of fractional and coronary flow reserve in predicting myocardial recovery in patients with previous myocardial infarction

AIMS The aim of the study was to evaluate the relation between fractional flow reserve (FFR) and simultaneously evaluated coronary flow reserve by thermodilution (CFRthermo), with the improvement of left ventricular (LV) function in patients with previous myocardial infarction (MI) undergoing percutaneous coronary intervention (PCI). METHODS AND RESULTS Study population consisted of 46 patients (mean age 53 +/- 7 years; 36 male) with previous MI and significant coronary stenosis undergoing PCI of infarct-related coronary artery. In all patients, we evaluated FFR and CFRthermo by single pressure/thermo wire during maximal hyperaemia before and immediately after PCI. We performed echocardiographic assessment of LV ejection fraction before and 6 months after PCI. Dobutamine stress echocardiography test was also performed before PCI. LV functional improvement was observed in 33/46 (72%) of patients. In patients with LV functional recovery in comparison with patients with no recovery, there was a significant difference in FFR before PCI (0.56 +/- 0.14 vs. 0.70 +/- 0.07, P < 0.001), improvement of FFR (0.35 +/- 0.14 vs. 0.21 +/- 0.07, P < 0.001), improvement of CFRthermo (1.3 +/- 0.6 vs. 0.5 +/- 0.3, P < 0.001), and CFRthermo after PCI (2.6 +/- 0.7 vs. 2.0 +/- 0.4, P < 0.001). When only parameters evaluated before PCI were taken into account, FFR before angioplasty (P = 0.001) and dobutamine-assessed viability (P = 0.006) were the most significant multivariate predictors of myocardial recovery. When all significant univariate parameters were evaluated, the most significant independent predictors for improvement in myocardial function were the improvement of CFRthermo during angioplasty (P < 0.001) and FFR before angioplasty (P = 0.002). CONCLUSION Simultaneous evaluation of FFR and CFRthermo provide significant complementary data on the improvement in myocardial function in patients with previous MI. However, the evaluation of FFR before angioplasty identifies viable myocardium that may recover following revascularization and may be used as an alternative to non-invasive testing.

New technique to seal a long giant coronary aneurysm with PTFE-covered stents: A case report

We report a case with a large aneurysm of right coronary artery (RCA) associated with coronary artery disease. The aneurysm was sealed with two PTFE‐covered stents using a sequential technique from proximal to distal to overcome the lack of long PTFE‐covered stents and existence of complex coronary anatomy. A bare metal stent was subsequently deployed to treat a lesion in the mid part of RCA. At 4‐month follow‐up, aneurysm was completely sealed and no restenosis occurred. Usage of sequential PTFE‐covered stents enables treatment of large coronary artery aneurysms.

Systemic rapamycin without loading dose for restenosis prevention after coronary bare metal stent implantation

Objectives: The aim of this study was to assess the role of short oral administration of rapamycin, without loading dose, in the reduction of restenosis rate after bare metal stent implantation. Background: Previous studies suggest that the administration of oral rapamycin reduces angiographic restenosis after bare metal stent implantation. Methods: This was prospective, open‐label study of 80 patients randomized to either oral rapamycin (2 mg/day for 30 days, starting within 24 hr of stent implantation) or no therapy after implantation of a coronary bare metal stent. The primary study end point was incidence of angiographic binary restenosis and late loss at six months. The secondary end points were target lesion revascularization (TLR), target vessel revascularization (TVR), and incidence of major adverse cardiovascular events (MACE) at 6 months. Results: Angiographic follow up was completed in 72/80 (90%) of patients. In the rapamycin group, the drug was well tolerated (22.5% minor side effects) and was maintained in 100% of patients. At six months, the in‐segment binary restenosis was 10.5% in rapamycin group vs. 51.4% in no‐therapy group, P < 0.001) and the in‐stent binary restenosis was 7.9% in rapamycin group vs. 48.7% in no‐therapy group, P < 0.001. The in‐segment late loss was also significantly reduced with oral therapy (0.29 ± 0.39 vs. 0.86 ± 0.64 mm, respectively, P < 0.001). Similarly, after six months, patients in the oral rapamycin group also showed a significantly lower incidence of TLR and TVR (7% vs. 22.7%, respectively, P = 0.039) and MACE (7% vs. 22.7%, respectively, P = 0.039). Conclusions: This study showed that the administration of oral rapamycin (2 mg/day, without loading dose) during 30 days after stent implantation significantly reduces angiographic and clinical parameters of restenosis.