Increased restenosis rates 12 months after coronary implantation of the sirolimus-eluting YUKON-choice stent compared to the paclitaxel-eluting TAXUS Stent

BACKGROUND

Previously the polymer-free sirolimus-eluting YUKON-Choice stent (A) has demonstrated noninferiority compared to the polymer-based paclitaxel-eluting TAXUS stent (B). To test for long-term equivalency in unselected real-world coronary lesions of various complexities, we retrospectively compared both stents.

METHODS

A total of 410 patients with symptomatic coronary artery disease (CAD) were treated with stent A (n = 205) or stent B (n = 205). Baseline clinical characteristics, lesion location, and length and the number of stents implanted per lesion were equally distributed. Clinical follow-up with assessment of major adverse cardiac events (MACE) and noncardiac deaths was obtained at 9 and 12 months.

RESULTS

Nominal stent diameter and nominal length of the stented segment were without differences between the groups. The incidence of MACE after 12 months was significantly higher in group A (35.1%) compared to group B (16.6%, P = .001). This was mainly due to increased rates of target-lesion revascularizations in group A (13.7%) vs group B (4.4%, P = .005). No significant differences in target-vessel revascularizations and non-target-vessel revascularizations were observed. In group B, 1 stent thrombosis was documented (0.5%) vs none in group A (P > .05); in each group 1 myocardial infarction (MI), but no cardiac deaths occurred; 3 noncardiac deaths in group A (1.5%) vs 7 in group B (3.4%) were observed (P = .3).

CONCLUSIONS

In contrast to our previous findings indicating no differences in MACE between patients treated with the polymer-free sirolimus-eluting YUKON-Choice stent and the polymer-based paclitaxel-eluting TAXUS stent at 6 months, we herewith show that 12 months after percutaneous coronary intervention (PCI) of real-world coronary lesions the YUKON stent appears to be inferior due to increased target-lesion revascularization (TLR) rates as a consequence of delayed restenosis.

Four-year results after brachytherapy for diffuse coronary in-stent restenosis: will coronary radiation therapy survive?

BACKGROUND

Prior to the introduction of drug-eluting stents (DES), diffuse coronary in-stent restenosis (ISR) was mainly treated by brachytherapy (BT), with good short-term and mid-term results. However, there exist limited data on the long-term effects of BT that justify its continuous use.

MATERIALS AND METHODS

Two hundred patients with diffuse ISR treated with intravascular BT were retrospectively followed over 4 years. Group A (n=134) was treated with the noncentered (90)Sr/Y BetaCath radiation system, whereas Group B (n=66) was treated with the centered 32P Galileo source wire system. Primary endpoints after 4 years were target lesion restenosis (TLS) and target lesion revascularization (TLR). Secondary endpoints were target vessel revascularization (TVR) and nontarget vessel revascularization (NTVR), as well as major adverse cardiac events (MACE).

RESULTS

Follow-up at 4 years yielded a TLS rate of 37.6% (Group A, 40.8%; Group B, 31.1%; P=.48). TLR was performed in 34.8% of patients (37.5% in Group A vs. 29.5% in Group B; P=.55). Ten percent of patients underwent coronary bypass surgery. Percutaneous coronary intervention was performed more often in Group A (27.5%) than in Group B (19.7%), while TVR was less frequent in Group A (10.0%) than in Group B (18.0%). NTVR was undertaken in 25.0% of Group A patients versus 21.3% of Group B patients, and MACE occurred in 1.7% of Group A patients versus 3.3% of Group B patients. These differences were not statistically significant (P>.05).

CONCLUSIONS

While excellent short-term and mid-term results after coronary BT are widely accepted, a high TLS rate can be observed after 4 years. The potential superiority of DES to BT will depend on the availability of long-term clinical data.

Closure of guide wire-induced coronary artery perforation with a two-component fibrin glue

Perforation or rupture of a coronary artery with subsequent pericardial effusion and cardiac tamponade is a potentially life-threatening complication of percutaneous coronary intervention (PCI). Several emergency treatment strategies exist to close the perforation including reversal of anticoagulation, prolonged balloon inflation, implantation of stent grafts, local injection of thrombogenic molecules, placement of microcoils, or open heart surgery. Here we report on a 66-year-old patient who underwent urgent PCI for acute stent thrombosis in the proximal LAD. The artery was reopened, a new stent implanted successfully, and a GPIIb/IIIa-antagonist was given. Shortly thereafter the patient suffered from cardiac tamponade requiring pericardiocentesis and pericardial drainage. The coronary angiogram indicated a severe guide wire-induced perforation and pericardial effusion originating from a distal diagonal branch segment. Prolonged balloon inflation did not stop the leakage. Therefore the monorail balloon was exchanged for an over-the-wire balloon. A two-component commercial fibrin glue consisting of fibrinogen and thrombin was rapidly but separately injected through the wire channel of the balloon into the distal segment of the diagonal branch. The coronary leak was successfully closed and the patient recovered quickly. In comparison with the previously reported cases of thrombin injection important differences should be noticed: (1) a two-component hemostatic seal was used without reversal of anticoagulation, (2) rapid injection instead of prolonged infusion of the hemostatic drugs was performed, and (3) the rescue technique was applied in a cath lab that routinely uses monorail catheter systems. Therefore we consider this a novel and effective approach for closure of coronary ruptures.

Effect of everolimus-eluting stents in different vessel sizes (from the pooled FUTURE I and II trials)

The everolimus-eluting stent (EES) has been shown to significantly decrease neointimal proliferation at 6 months compared with the bare metal stent (BMS) in patients with de novo coronary lesions. We report mid-term outcomes based on different vessel sizes in the combined FUTURE I and II trials. In the prospective, randomized, FUTURE I trial (single center) and expanded FUTURE II trial (multicenter), 106 patients (107 lesions) were randomized to EESs (n = 49 lesions) or BMSs (n = 58 lesions). Patients were categorized into 3 groups based on preprocedure reference diameter as assessed by quantitative coronary angiography (small vessel < 2.75 mm, medium vessel 2.75 to 3.25 mm, and large vessel > 3.25 mm). At 6-month follow-up, EESs decreased in-stent late lumen loss (decreased rate range of 78% to 94%), resulting in significantly larger minimum lumen area as assessed by intravascular ultrasound (increased range of 34% to 42%) compared with the BMS across all vessel sizes. There were no cases of in-stent restenosis with EESs at any vessel size but 8 cases with BMSs (5 in small vessels). No stent thrombosis, aneurysm formation, or late stent incomplete apposition was observed in any group. The EES appears to be effective for treatment of de novo coronary lesions in decreasing neointimal proliferation at 6-month follow-up compared with BMSs, regardless of vessel size.

One-Year Clinical Outcomes After Complete Arterial Coronary Revascularization

BACKGROUND

Conventional coronary bypass surgery applies single internal mammary arteries and saphenous vein graft conduits for revascularization of occluded coronary arteries. While the use of saphenous vein grafts is limited by early graft occlusion, little data exist on clinical experiences with complete arterial revascularization.

PATIENTS AND METHOD

From January 2003 to July 2004, 390 patients were transferred from Red Cross Hospital Cardiology Center to the Rotenburg Cardiovascular Center for coronary bypass operation. From these patients, 200 were selected for complete arterial revascularization. Mean age of the patients was 66.7+/- 8.0 years; 80.5% were male; 68.5% had triple-vessel disease, 31% had two-vessel disease, and 0.5% had single-vessel disease; 32% were diabetic; and 6.5% had a previous bypass operation. Left ventricular ejection fraction was >50% in 85.5% and 30-50% in 14.5%. Double internal mammary artery grafts were used in 98% and single internal mammary artery grafts in 2%. In 51%, the right internal mammary artery was connected with the left internal mammary artery as a T-graft and in 17%, it was used as a free aortocoronary graft. Radial artery grafts were used in 4%. The average number of anastomoses per patient was 3.4.

RESULTS

During the primary in-hospital stay, 1.5% of the patients had to undergo reoperation, 3.5% had myocardial infarctions, 3.5% had wound healing complications, 1.0% experienced an ischemic stroke, and 1 patient died following an acute myocardial infarction. At 12 months, 1.0% underwent percutaneous reinterventions, 0.5% had to be reoperated, 0.5% had a myocardial infarction, and 1.0% died. The actuarial survival rate at 12 months was 99%.

CONCLUSION

When both the internal mammary arteries are used as the preferred surgical strategy, complete arterial revascularization can be performed with excellent clinical results over 12 months.

Percutaneous Saphenous Vein Graft Interventions with and without Distal Filter Wire Protection

BACKGROUND

Embolic protection during SVG interventions using distal balloon occlusion and aspiration has shown to reduce periprocedural complications compared to unprotected SVG interventions. A similar effect is expected from filter wires.

PATIENTS AND METHODS

A total of 174 SVG interventions carried out with (group A; n=87) or without distal filter wire protection (group B; n=87) were retrospectively matched for the location of distal graft anastomosis and analyzed for baseline and procedural characteristics, for TIMI flow grade before and after PCI, for the post-procedural CK elevation, and for major adverse cardiac events at 30 days and 6 months (primary end point). Location of distal graft anastomosis was the left anterior descending artery in 19.6%, the left diagonal branch in 6.9%, the left marginal branch in 17.2%, the left posterolateral branch in 24.2%, the mid-segment of the right coronary artery in 28.7%, and the posterior descending artery in 3.4%.

RESULTS

Baseline clinical demographics showed no relevant differences between both the groups. Mean age of vein grafts was 11.7+/- 4.3 years in group A versus 10.6+/- 4.9 years in group B (P=0.15). The number of stents per lesion was 1.4+/- 0.8 in group A versus 1.0+/- 0.8 in group B (P<0.01). The total length of stents was 32.2+/- 16.2 mm in group A versus 20.9+/-12.1 mm in group B (P<0.01). TIMI flow grade pre was 2.5+/-0.8 in group A versus 2.7+/- 0.6 in group B (P<0.05). TIMI flow grade post was 2.9+/- 0.3 versus 2.9+/- 0.2. Improvement of TIMI flow grade after SVG intervention was 0.4+/- 0.7 in group A versus 0.2+/- 0.6 in group B (P<0.05). Post-procedural CK-MB elevations were observed in 17 patients of group A versus 14 patients of group B (P=0.18). At 30 days, there were no myocardial infarctions (MIs) and no deaths in either group. One patient of group A had to be reoperated and four patients of group A underwent repeat PCI (4.6%) versus one patient of group B (1.2%). At 6 months, there were again no MIs and no deaths in either group. Target lesion revascularization rate was 17.3% in group A versus 11.5% in group B (P <0.02).

CONCLUSION

When distal filter wire protection is used in high risk SVG lesions, the clinical outcome of percutaneous interventions may be equal to low risk SVG lesions without filter wire protection.

Comparison of a centered 32P source wire system with a noncentered 90Sr/Y brachytherapy system for intracoronary β-radiation following PCI of diffuse in-stent restenosis

BACKGROUND

We investigated the potential impact of differences in effective radiation dose between the centered Guidant 32P source wire system and the noncentered Novoste 90Sr/Y BetaCath system on clinical and angiographic outcomes of intracoronary brachytherapy for the prevention of in-stent restenosis.

METHODS

From 10/00 to 05/04, a total of 400 patients underwent percutaneous coronary intervention (PCI) with brachytherapy for diffuse in-stent restenosis at our institution. Following balloon dilatation, patient Group A (n=200) was treated with the centered 32P Galileo source wire system, patient Group B (n=200) was treated with the noncentered 90Sr/Y BetaCath radiation system. In Group A, the prescribed dose of 20 Gy was applied in 1-mm depth of the vessel wall. In Group B, the prescribed dose of 18.4 Gy was applied for visual reference vessel sizes >2.7 and <3.35 mm, 23 Gy for >3.36 and <4.00 mm, and 25.3 Gy for >4.00 mm, each calculated at a distance of 2 mm from the center line of the radiation source. Patients received aspirin and clopidogrel over 12 months. Primary endpoint was target lesion revascularization (TLR) at 6 months. Secondary endpoints were the binary restenosis rate and major adverse cardiac event (MACE) at 30 days and 6 months.

RESULTS

At 30 days, one patient of each group underwent PCI at a nontarget lesion (0.5%). At 6 months, MACEs were equally distributed in both groups. Target lesion revascularization at 6 months was 5.9% in Group A and 9.2% in Group B (P=.08). Binary angiographic restenosis rate at 6 months was 5.5% in Group A and 11.2% in Group B (P=.014).

CONCLUSION

Intracoronary beta-radiation using the centered 32P source wire system yielded a significant reduction of recurrence rate compared to the noncentered 90S/Y BetaCath system after PCI of diffuse in-stent restenosis. There was a nonsignificant trend toward reduction of TLR among patients treated with the centered 32P source wire system.

Relationship between Size of Myocardial Infarctions Assessed by Delayed Contrast-Enhanced MRI after Primary PCI, Biochemical Markers, and Time to Intervention

BACKGROUND

The quantitative assessment of myocardial infarctions using delayed contrast-enhanced magnetic resonance imaging (MRI) has recently been validated using postmortem histopathological animal studies. In a prospective study, we investigated the correlation between infarct size as assessed by delayed contrast-enhanced MRI, elevation of creatine kinase (CK), and c-reactive protein (CRP) as well as the time from onset of symptoms to intervention.

METHODS

Four to 10 days after immediate PCI in 45 acute ST-segment elevation myocardial infarction (STEMI) patients (<24 hour) with stenting of the infarct-related artery and treatment with abciximab, we performed gadolinium contrast-enhanced three-dimensional inversion recovery gradient-echo MR sequences with complete coverage of the LV-myocardium in short-axis slices. The mass of infarcted tissue based on the volume of hyperenhanced myocardium was calculated and linear regression analysis was performed to assess the correlation between absolute size of infarctions (g) as well as relative size (LV%) with peak values of CK, CRP, and the time to PCI.

RESULTS

There was a significant correlation between absolute size of infarctions (g) and peak CK values (r = 0.72; P < 0.001) as well as the relative size (LV%) and peak CK (r = 0.77; P < 0.001). No correlations were found between absolute size (r = 0.33) as well as relative size (r = 0.27) of infarctions and peak CRP. There was also no correlation between absolute (r = 0.29) as well as relative size of infarctions (r = 0.27) and the time from onset of symptoms to PCI.

CONCLUSIONS

In patients with acute STEMI (<24 hour) undergoing immediate PCI with stenting and treatment with abciximab, peak CK values correlated well with infarct size as assessed by delayed contrast-enhanced MRI. There were no correlations between infarct size and peak CRP as well as the time to intervention.

Clinical Experiences Using Everolimus-Eluting Stents in Patients with Coronary Artery Disease

Despite the growing use of drug-eluting stents, restenosis remains to occur especially in high risk subgroups like patients with diffuse in-stent restenosis. This observation is supporting the search for new and potentially even more effective drug eluting stent systems. Everolimus has been used in conjunction with a new bioabsorbable polymer and gave promising results in initial clinical studies. In FUTURE I, a single-center, single-blinded randomized safety and feasibility study enrolling 15 patients with bare metal stents and 27 patients with everolimus-coated stents, 30-day MACE rate was 0% in both groups. In-stent late loss at six months was 0.83 mm in the control group and 0.10 mm in the everolimus group (p < 0.0001). In FUTURE II, a randomized multi-center study, a total of 64 patients were enrolled confirming safety and feasibility. After 6 months late loss was 0.85 mm in the control group and 0.12 mm in the everolimus group (p < 0.001).

Long-term outcome after implantation of bare metal stents for the treatment of coronary artery disease: rationale for the clinical use of antiproliferative stent coatings

BACKGROUND

The widespread use of drug-eluting stents in patients with coronary artery disease (CAD) is hampered by unequal regulations for reimbursement. Identification of patients with maximal benefit from this technology may be achieved by assessing long-term clinical outcome after implantation of uncoated bare metal stents.

PATIENTS AND METHODS

A consecutive series of 1,000 patients with CAD treated with bare metal coronary stents of various designs from January 1995 to December 1995 was retrospectively followed over 4 years. The primary end points of the study were major adverse cardiac events.

RESULTS

The mean age of patients was 62 +/- 10.3 years, 77.5% were male, and 18% were diabetic. Clinical follow-up was obtained in 821 patients (82.1%) after 4.6 +/- 1.1 years. During this period of time, 31.8% were admitted for repeat PCI, 15.1% underwent CABG operation, 3.5% had myocardial infarctions, and 3.7% died. At 4 years, 46.3% of diabetic patients survived without event versus 57.6% of nondiabetic patients (P < 0.05). Patients with CAD I survived without event in 65.3% versus 54.0% of patients with CAD II and 48.5% of patients with CAD III (P < 0.02).

CONCLUSION

Implantation of uncoated stents provides the worst long-term clinical outcome in patients with diabetes and those with multivessel CAD. Both groups of patients appear to be primary candidates for the use of drug-eluting stents.

Comparison of stainless steel stents coated with turbostratic carbon and uncoated stents for percutaneous coronary interventions

BACKGROUND

Stent coating with turbostratic carbon was supposed to minimize the local inflammatory response after stent implantation and to thereby also reduce the rates of restenosis and clinical events.

METHODS AND RESULTS

From October, 1999 to February, 2002, a total of 329 patients with symptomatic coronary artery disease (CAD) eligible for single-lesion PCI were randomized for implantation of either a CarboStent (C; n = 168) or a stainless-steel stent (S; n = 161). The stainless-steel stents were Tristar stents in 60.2%, Tetra stents in 17.4% and Penta stents in 22.4%. Both groups showed no differences in baseline clinical and angiographic characteristics. Angiographic follow-up (FU) was obtained after 6 months in 287 patients (87.2%), clinical FU in 295 patients (89.7%). With the exception of a smaller post-procedure minimal luminal diameter (MLD) in the C group (2.59 0.43 mm versus 2.72 0.46 mm in the S group; p = 0.01), there were no significant differences between the C and S groups in lesion length (10.28 4.45 mm versus 10.37 4.79 mm, respectively), reference diameter (2.92 0.59 mm versus 2.89 0.53 mm, respectively), pre-procedure MLD (0.77 0.36 mm versus 0.84 0.36 mm, respectively), MLD at FU (1.67 0.64 mm versus 1.68 0.57 mm, respectively), late loss (0.93 0.63 mm versus 1.05 0.59 mm, respectively), late loss index (0.51 0.32 versus 0.57 0.32, respectively) and restenosis rate (18.1% versus 20.6%, respectively). There were also no significant differences regarding major adverse cardiac events (MACE) between the C and S groups, i.e., occurrence of death (0% versus 0.7%, respectively), myocardial infarction (0% versus 0.7%, respectively), coronary artery bypass graft (0.7% versus 1.4%, respectively) and target lesion revascularization (16.4% versus 21.5%, respectively).

CONCLUSION

Coronary stents coated with turbostratic carbon gave no clinically relevant reduction of in-stent restenosis and MACE rates when compared to uncoated stents.

Diffuse in-stent restenosis

Stent restenosis, especially the diffuse pattern, has developed into a significant clinical and economical problem. It has been estimated that up to 250,000 patients developed in-stent restenosis in 2,000 alone, two thirds of them can be expected to have diffuse in-stent restenosis, which is difficult to treat because of high recurrence rates. None of the conventionally available interventional treatment modalities provides optimal long-term results. Intravascular radiation therapy is currently the only effective percutaneous therapy for combating in-stent restenosis. Late thrombotic complications have largely been eliminated by extended antiplatelet regimens. Geographical miss, a major reason for recurrence of in-stent restenosis after brachytherapy, can be reduced by an improved radiation technique. The first preliminary data on drug-eluting stents, showing only minimal neointimal proliferation at 6-month postimplantation, could represent a major breakthrough in the quest to solve restenosis.

[Balloon angioplasty of stent restenosis: early and late results of first and second PTCA in focal and diffuse stenosis]

From January 1996 until February 1997 6,376 patients were treated by our group with PTCA and 3,859 (60.5%) received one or several stents. An angiographic followup was achieved in 63% of the patients with 1,267 experiencing restenosis (32.8%). Of those being treated with re-PTCA 302 were randomly selected for further analysis. In-stent-restenosis was treated with rotablator in 8 patients (2.7%), with eximer laser in 21 (7.0%) and with another stent in 48 patients (15.9%). 225 patients (74.4%) of this subselection were treated with balloon-angioplasty only. Mean patient age was 63 +/- 10.2 years, 401 stents had been implanted (42.5% Wiktor, 13.7% Jomed Sito, 12.3% ACS Multlink, 9.5% GR II, and some others), the number of stents per patient was 1.68, mean stent length 28.5 mm, mean stent diameter 3.01 +/- 0.3 mm, the time since implantation 142 +/- 76 days. The recurrence appeared as restenosis in 199 patients (88.4%) and as a chronic stent occlusion in 26 (11.6%). In-stent-restenosis was discovered in 94.7% within the stent and was of focal appearance (restenosic lesion of < or = 5 mm) in 28.5% and diffuse (> 5 mm) in 71.5%. Balloondilatation (balloon:artery = 1:1; maximal pressure 11.7 +/- 3.3 bar) was successfull in 98% of the stenotic lesions and in 18/26 of the chronically occluded stents (definition of success: residual stenosis < 50%, no major complications). The stenosis decreased from 82.2% to 20.5% (12.8% in focally stenosed vessels and 23.6% in diffuse restenosis). Complications were death in 0.9%, Q-MI in 0% CABG in 0.9%, Non-Q-MI in 2.4%, subacute stent thrombosis in 0.5% and groin bleeding in 1.8%. A clinical follow up after 151.7 +/- 87.7 days was achieved in 98.6% and an angiographic follow up in 69.1% of the patients: 1.9% had died (2/4 due to noncardiac disease), no MI, 6.2% CABG and 31% PTCA (TLR 37.2%). A second restenosis within the stents ocurred in 27.9% of those with focal disease and in 44.3% of those with diffuse in stent restenosis.

CONCLUSIONS

Restenosis within stents may occurr in about 30% of unselected patients. In 2/3 these stenoses appear diffuse and in 10% they appear as chronic occlusions. Re-PTCA with balloons is rather simple with a high success rate (even in chronic stent occlusions) and a low complication rate. The incidence of a second restenosis is acceptably high in focal lesions but appears unacceptable in patients with diffuse in-stent-restenosis. Thus the indication for stenting should be restricted to patients with clear cut advantage over balloon-angioplasty alone, e.g. threatening closure, chronic occlusion, old savenous veingraft and proximal LAD stenosis.

[From surgical to interventional standby?]

Life threatening Q-infarction because of bypassgraft occlusion may occurr in 5-8% of the patients during the first days after CABG, and most patients are treated by immediate reoperation. This treatment may however be delayed because operating rooms might not be available immediately. We prospectively studied the feasability and safety of immediate coronary angiography and PTCA, if appropriate, in patients with severe ischemic in-hospital complications after CABG. From January till December 1995 1263 patients had CABG: mean age 64.9 +/- 10 y, 24% female, 7.1% emergencies (CABG < 24 h after coronary angiography). A 24 hours interventional standby was provided to perform immediate catheterization and PTCA in patients with signs of evolving myocardial infarction after CABG (ST-elevation in > or = 2 leads and hemodynamic compromise or new LV hypocinesia in the transoesophageal echocardiogramm).

RESULTS

3/1263 patients had immediate reoperation without angiography. 55/1263 patients were catheterized, all within 1 hour after the onset of Stelevation. 14/1263 had normal grafts and complete revascularization. Their ischemia was either transient (spasm) or the ECG was misinterpreted (pericarditis). Catheterization caused no severe complications. 2 patients had major bleeding at the puncture site. 41 patients presented with envolving Q-MI: 1 patient had immediate reoperation, 29 patients received immediate PTCA and 11 patients were treated medically. 8/29 PTCA-patients were in cardiogenic shock. We dilated 4 IMA-anastomoses, 3 distal veingraft anastomoses, 18 native vessels with occluded veingrafts and 4 native vessels, having not been grafted. Angiographic success was achieved in 20/29 (69%), clinical success in 65% (residual stenosis < 50%, no severe complications during hospital stay). 2 patients died during the first 30 days (none due to the PTCA procedure or PTCA-related delay of reoperation), Q-MI occurred in 2/29, NonQ-MI in 7/29, reoperation appeared necessary in 4/29, no bleeding complications were noticed.

CONCLUSIONS

Immediate coronary angiography after CABG is feasable and safe. Salvage-PTCA early after CABG is an alternative treatment in patients with evolving Q-MI. Interventional standby might therefore be useful for institutions with a busy cardiac surgical program.

Results of Micro stent implantations in coronary lesions of various complexity

Micro stents appear to be especially suitable for the safe treatment of complex coronary lesions and adverse vessel morphology. Stenting of lesions with type C morphology is associated with a higher restenosis rate than stenting of less complex coronary obstructions.

Randomized comparison of angioplasty of complex coronary lesions at a single center. Excimer Laser, Rotational Atherectomy, and Balloon Angioplasty Comparison (ERBAC) Study

BACKGROUND

The purpose of this study was to test whether coronary revascularization with ablation of either excimer laser or rotational atherectomy can improve the initial angiographic and clinical outcomes compared with dilatation (balloon angioplasty) alone.

METHODS AND RESULTS

At a single center, a total of 685 patients with symptomatic coronary disease warranting elective percutaneous revascularization for a complex lesion were randomly assigned to balloon angioplasty (n = 222), excimer laser angioplasty (n = 232), or rotational atherectomy (n = 231). The primary end point was procedural success (diameter stenosis < 50%, absence of death, Q-wave myocardial infarction, or coronary artery bypass surgery). The patients who underwent rotational atherectomy had a higher rate of procedural success than those who underwent excimer laser angioplasty or conventional balloon angioplasty (89% versus 77% and 80%, P = .0019), but no difference was observed in major in-hospital complications (3.2% versus 4.3% versus 3.1%, P = .71). At the 6-month follow-up, revascularization of the original target lesion was performed more frequently in the rotational atherectomy group (42.4%) and the excimer laser group (46.0%) than in the angioplasty group (31.9%, P = .013).

CONCLUSIONS

Procedural success of rotational atherectomy is superior to laser angioplasty and balloon angioplasty; however, it does not result in better late outcomes. The role of plaque debulking before balloon dilatation in percutaneous coronary revascularization remains to be fully defined.

[Results after coronary bypass operation]

OBJECTIVE

To determine the influence of various risk factors on 30-day postoperative mortality rate of aortocoronary bypass operation at different centres.

PATIENTS AND METHODS

Data on 227 patients (179 men, mean age 63 [40-87] years; 48 women, mean age 68 [44-81] years), 219 first operations, 8 second operations) were retrospectively analysed. In all patients the indications for aortocoronary bypass surgery had been established in the last 3 months of 1993. The operations had been performed at six cardiac centres in Germany (five in Hessen [H1-H5]) and in three hospitals elsewhere in Europe outside of Germany (E1-E3).

RESULTS

The operative mortality was relatively high (5.3%), 152 patients (67%) presenting with one or more risk factors accounting for an increased perioperative mortality. The mortality rate was significantly higher for: clearly impaired left ventricular function (ejection fraction < 40%): 20 vs 3% with an ejection fraction > or = 40% (P < 0.001); emergency operation: 16.6 vs 2.7% for elective operation (P < 0.001); advanced age (> or = 70 years): 10.9 vs 3.1% for younger patients (P < 0.025); and unstable angina: 9.2 vs 2.9% with stable angina (P < 0.05). Most of the bypasses were done with the internal mammary artery (63.9%, usually combined with venous bypasses (exclusive use of venous bypasses in 35.2%), but the proportion of arterial bypasses differed greatly between centres (96% in H3, 19% in H4).

CONCLUSIONS

(1) Aortocoronary bypass operations are done on many patients with important risk factors, resulting in a relatively high 30-day postoperative mortality rate. (2) The proportion of internal mammary artery bypasses markedly differs between centres in Hessen.

[The recanalization of chronic coronary artery occlusions: what factors influence success?]

Between January 1986 and June 1990, recanalization with guide-wire and balloon angioplasty (PTCA) was attempted in 509 patients (416 men, 93 women; mean age 57.5 +/- 9 years) with chronic coronary artery occlusions. The data recorded were analysed to determine the factors which influenced the outcome. The intervention was initially successful in 284 patients (55.8%; circumflex branch: 50%; right coronary artery: 52%; venous bypass graft: 50%; anterior interventricular branch: 64%). The success rate was markedly reduced if (1) the occlusion had persisted for more than 6 months (9.5%; P < 0.001); (2) occlusion had occurred at or after a vessel kink (28.5%; P < 0.001); (3) there had been no vessel "stump" (36%; P < 0.01) and (4) the occlusion was longer than 10 mm (40.7%; P < 0.05). The success-rate was higher if (1) intracoronary anastomoses were absent (61.2%); (2) occlusion had occurred in a straight vessel (62.6%); (3) there had been a vessel stump (64%); (4) the occlusion had persisted for less than 4 weeks (68.5%) and (5) the length of occlusion was < or = 10 mm (75.8%).-These data indicate that the success of PTCA after chronic coronary artery occlusion depended on the site of occlusion, its duration and length, absence of orthograde collaterals and the presence of a vessel stump. Knowing the extent of these factors helps in delineating the indications.

Randomized trial comparing two devices: the Palmaz-Schatz stent and the Strecker stent in bail-out situations

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.

[The long-term success after coronary angioplasty in old age]

Long-term results of coronary angioplasty (CAP) were compared between two age-groups of patients. Group 1 had 227 patients (158 men, 69 women) with a mean age of 70 (65-88) years, group 2 had 717 patients (611 men, 106 women), mean age 54 (20-64) years. Unstable angina was more common in group 1 than group 2 (48.9 vs 37.7%, P < 0.05). Multi-vessel disease was present in 50.7% of those in group 1 and 41.9% in group 2. Primary success of CAP was similar in the two groups (group 1: 88.1%, group 2: 90.5%). The long-term effect at the first follow-up angiography 3-4 months after CAP was slightly less favourable in group 1 than 2 (54.9 vs 58.3%; difference not significant). However, there were more patients with unstable angina in group 1. Thus the angiographic long-term results were worse in the older patients (44.6 vs 60.1%; P < 0.05), while there was no difference between the two groups as regards stable angina (64.7 vs 57.2%). After a second CAP (because of recurrence), the long-term angiographic effect was, if anything, slightly better in the older patients (87.0 vs 77.1%). The death-rate (cardiac causes of death) up to one year after CAP was comparable in the two groups (1.7 vs 0.8%), as was the rate of non-fatal myocardial infarction (2.2 vs 1.3%). These data indicate that clinical and angiographic long-term success after CAP is comparable in older and younger patient groups and age alone does not present a higher risk.

[Long-term results of coronary angioplasty in relation to vessel size]

Repeat angiography was performed after 3-4 months in 927 of 1386 consecutive patients (67%) who had a successful percutaneous coronary angioplasty (PTCA) between 1986 and 1988. The degree of coronary artery stenosis was determined angiographically before PTCA, immediately after and 3-4 months later. Patients were assigned to one of four groups according to balloon diameter at dilatation: Group 1: 1.5-2.0 mm; group 2: 2,5 mm; group 3: 3.0 mm; group 4: 3.4-4.2 mm. Vessel wall proliferation occurred in all four groups after PTCA. In patients with angiographically demonstrated recurrence (first recurrence: 308 patients, second recurrence: 43 patients) another balloon dilatation was undertaken and a repeat angiography 3-4 months later. Long-term success rate (less than 50% stenosis) differed significantly according to the post-PTCA vessel diameter: 48% in group 1, 63% in group 2, 66% in group 3 and 80% in group 4 (analysis of variance: P less than 0.001). PTCA thus produces better long-term results in large than in small vessels.

[Main branch stenosis following aortic valve replacement]

Three patients developed left main stem stenosis within some months after aortic valve replacement. In all of them diagnosis was confirmed by angiography and bypass surgery was performed successfully. Left main stem stenosis is a rare complication of aortic valve replacement and is due to cannulation and perfusion of the coronary arteries. The mechanism is probably injury of the vessel wall due to the perfusion-catheter, followed by intimal hyperplasia. A similar mechanism is assumed for restenosis after transluminal coronary angioplasty.

[Acute vascular occlusion caused by percutaneous transluminal coronary angioplasty: early and late results of repeat-PTCA]

Acute vascular occlusion after percutaneous transluminal coronary angioplasty (PTCA) often necessitates a prompt aortocoronary bypass-operation (CABG). Alternatively, a re-PTCA can be attempted. In 1500 consecutive patients there was acute symptomatic occlusion due to PTCA 5 min to 16 h after the operation in 47 cases (3.1%). An immediate re-PTCA was attempted in all cases.

RESULTS

Reopening was successful in 43 of 47 cases (91%): in 15 patients (30%) within 30 min, in 36 patients (68%) within 60 min and in 42 patients (89%) within 90 min. In eight patients there was early re-occlusion 30 min to 20 h after re-PTCA, necessitating acute CABG in four patients. In 35 patients with re-PTCA the vessel remained open. Re-stenosis occurred within 1 to 10 days in 10 patients, and in additional 12 patients after 2-4 months. In most cases an additional PTCA was successful.

COMPLICATIONS

Six patients had an emergency CABG (three with an exchange wire as a stent in the dissected coronary artery). Three patients died (one after CABG); 14 patients experienced myocardial infarction (30%) (in three of these 14 the infarct was large).

CONCLUSION

Acute vascular occlusion after PTCA can successfully be treated by re-PTCA in four of five cases. However a rate of re-stenosis of about 60% is to be anticipated. Reperfusion with re-PTCA is fast and in these patients with transmural ischemia there are obviously less complications in comparison to emergency CABG after PTCA. 60% of the patients remain symptom free or markedly improved and without infarction or emergency CABG after 4 months.

[The results after prosthetic aortic valve replacement. What effect does old age have?]

Data were retrospectively analysed of 149 consecutive patients with aortic valve stenosis (91 males and 58 females; mean age 64 [27-86] years) who had a prosthetic valve implanted between 1986 and 1988. The overall operative mortality rate was 3.4%, the one-year mortality rate was 4.7%. Operative mortality rate for those aged 27-74 years was 1.7% (2 of 120), but 10.3% (3 of 29) for those aged 75 to 86 years (P less than 0.05). None of the patients in clinical grade III (NYHA classification) died within 30 days of the operation. Among those in grade IV the operative mortality rate was 15.8% (3 of 19) for those aged 75-86, but 4.0% (2 of 50) for those aged below 75 years (P less than 0.05). Valve replacement in symptomatic aortic stenosis with a prosthetic valve is today the method of choice. Operative mortality rate is low, even for patients of advanced age, particularly if the operation is done early.

[Long-term success of coronary angioplasty after repeated treatment]

To ascertain the long-term results after second and third angioplasties for coronary stenosis the coronary angiograms from 1504 consecutive patients with coronary heart disease (1211 men, 293 women, mean age 57 [27-82] years) were retrospectively surveyed. A good initial response (at least 20% reduction in stenosis) was achieved in 295 out of 306 second angioplasties (95.5%), and in all 36 third angioplasties. Viewed overall, these results are significantly better (P less than 0.005) than those achieved at the initial angioplasty (1386 out of 1504 patients; 92.2%). The reduction in the severity of the stenosis achieved at the second angioplasty (from 86 to 24%) and at the third angioplasty (from 86 to 26%) was the same as at the first angioplasty (from 88 to 28%). Serious complications after the first angioplasty were infrequent (death in 0.2%, emergency bypass in 0.4%, myocardial infarction in 0.5%), and no complications were noted after second and third angioplasties. A good long-term outcome (at least 20% reduction in stenosis at 3-4 months) was slightly more frequent after the second and third angioplasties (103 out of 170 [60.6%] and 14 out of 17 patients, respectively) than after the first intervention (532 out of 926 patients; 57.5%). In keeping with these results, the degree of stenosis found at follow-up angiography was significantly lower (first intervention 54.8%, second intervention 50.3%, third intervention 36.9%). There were only 57 patients (3.8%) who ultimately required operative treatment. These figures indicate that the probability of a good long-term outcome from coronary angioplasty increases each time the stretching operation is repeated. Only a very small proportion of patients will require bypass surgery.

[Treatment of coronary heart disease in the aged. When balloon dilatation, when surgery?]

Data from 3029 consecutive patients (2474 men, 555 women, mean age 59 [20-88] years) in whom coronary heart disease had been diagnosed by coronary angiography were studied with the object of identifying those patients in the older age group who are suitable for treatment by balloon angioplasty. There were 884 patients with a mean age of 70 (65-88) years, and 2145 patients with a mean age of 54 (20-64) years. Single vessel disease was less common in older patients (30% vs 44%; P less than 0.001), double vessel disease was equally common in both groups (28% vs 30%) and triple vessel disease was commoner in the elderly group (42% vs 26%; P less than 0.001). For elderly patients with single vessel disease conservative treatment was chosen in 50%, angioplasty in 49% and operative treatment in only 1%. Of elderly patients with involvement of two arteries, 44% were treated conservatively, 40% by angioplasty and 16% surgically. Of elderly patients with triple artery disease, 23% were treated conservatively, 8% by angioplasty and 69% operatively. This pattern was similar to that among younger patients. The success rate and the incidence of complications after percutaneous transluminal coronary angioplasty were similar in both age groups. In elderly patients with disease of only one or two coronary arteries the prospects of success and the risks are comparable to those in younger patients, but patients with triple artery disease often need bypass surgery.

[Protective function of collaterals in percutaneous transluminal coronary angioplasty]

With increasing application of PTCA, it will become necessary to identify patients (p) who can be dilated without expensive surgical standby. In 82 p with angina pectoris and stress-induced ischemia and without transmural myocardial infarction, the following parameters were measured during coronary angioplasty (PTCA): angina pectoris (AP), epicardial ST-segment displacement (via long wire), and aortic pressure. In 26 p, the affected vessel showed retrograde filling (A) via collaterals (CL). In 24 p CL were identified without retrograde filling (B) and 32 p were without CL (C). The balloon was inflated three to eight times over periods of 30 to 90 s. [table; see text]

CONCLUSIONS

In vessel occlusion caused by PTCA, a myocardial infarction will occur in more than 80% of p without visible CL, and rarely in the presence of CL. Therefore, PTCA of vessels with retrograde filling appears safe. Furthermore randomized studies are necessary to determine if strict surgical standby is required in such cases.

Long-term treatment of severe chronic heart failure with captopril: a double-blind, randomized, placebo-controlled, long-term study

Twenty-three patients with severe heart failure (NYHA classes III and IV) on treatment with digitalis and diuretics were additionally treated in a randomized double-blind study over a 6-month period with captopril (n = 12; mean daily dose 84 mg) or a placebo (n = 11) and were then reexamined. In the captopril group, the left-ventricular filling pressure decreased by 9 mm Hg (from 23 to 14) at rest and 6 mm Hg (from 35 to 29) during exercise. In the placebo group, there was an increase of 4 mm Hg (from 25 to 29) at rest and 7 mm Hg (from 33 to 40) during exercise; p less than 0.01 (p less than 0.01). In the captopril group, the cardiac index at rest increased 0.7 1/min/m2 (from 2.1 to 2.8) and during exercise 1.2 1/min/m2 (from 2.8 to 4.0). In the placebo group, the increase in cardiac index was considerably less pronounced at rest (= 0.2 1/min/m2; from 1.9 to 2.1) and during exercise (= 0.1 1/min/m2; from 2.7 to 2.8); p less than 0.02 (p less than 0.01). The improved cardiac output had a beneficial effect on the renal blood flow. Hippuran clearance increased by 46 ml/min (from 271 to 318), whereas in the control group it decreased 25 ml/min (from 259 to 234) (p less than 1.02). Both the heart rate and the arterial blood pressure remained constant, whereas the decrease in peripheral vascular resistance was definitely more pronounced in the captopril group (= 562 dyne X s X cm-5, from 1,841 to 1,279) than in the placebo group (= 123 dyne X s X cm-5, from 1,834 to 1,710; p less than 0.02). The heart volume, assessed radiographically, increased slightly in the placebo group, and the left-ventricular end-diastolic diameter remained constant in both groups. In the course of the study, two patients died in the captopril group and three in the placebo group. After six months, eight patients in the captopril group and three in the placebo group had improved by at least one NYHA category. The beneficial effects of captopril are due to its inhibitory effect on the renin-angiotensin system as well as to the inhibition of sympathetic stimulation. Consequently, in the captopril group the quantity of plasma norepinephrine decreased by 188 ng/ml (from 430 to 618); p less than 0.03. The indirect vasodilation caused by this mechanism leads to persistent unloading of the myocardium and an improvement in heart failure without loss of action by counterregulatory mechanisms.

[Regional myocardial ischemia in the conscious dog under echocardiography control]

Regional myocardial dysfunction is a very sensitive and early parameter of myocardial ischemia. One minute occlusion of the left anterior descending (LAD (n = 8) and circumflex coronary artery (CCA) (n = 8) by means of hydraulic occluders was performed in 10 chronically instrumented conscious dogs. In a left ventricular cross-section diastolic and systolic area (DA, SA) and area shortening (AS) as well as regional function of 6 radial sectors were evaluated with 2D echocardiography. After occlusion of the LAD, SA increased by 33% (p less than 0.05), AS decreased by 22% (p less than 0.05) while the DA remained unchanged. In 2 of 6 radial sectors (anteroseptal) shortening decreased by 41% (p less than 0.01) and 54% (p less than 0.001) respectively. Occlusion of the circumflex coronary artery CCA caused an increase in DA (18%) and SA (33%) and a reduction of AS by 24% (p less than 0.01). Contraction of the anterior wall (sectors 2 and 3) was reduced by 61% and 57% (p less than 0.001). In the same animal 10 one minute occlusions of the LAD with 5 min intervals of reperfusion caused a reproducible depression of sector 6 (septal) from 63.2 +/- 5.4% to 16.3 +/- 3.4%. In another animal 11 one minute CCA occlusions with 5 min intervals of reperfusion reproducibly decreased the contraction of sector 3 (anterior) from 85.2 +/- 6.7% to 21.4 +/- 17.0%. 2D-E allows a reproducible estimation of regional left ventricular dysfunction during ischemia. Our model has the advantage that numerous studies can be performed in the same animal, so that the results can be compared intraindividually.

Aldosterone and prolactin responsiveness after prolonged treatment of congestive heart failure with captopril

After long-term captopril treatment, an inappropriate increase in aldosterone levels has been observed in hypertensive patients. It is not known, whether a similar change would occur in patients with severe congestive heart failure, and whether it is due to a decrease in endogenous dopaminergic inhibition of aldosterone secretion or to aldosterone stimulation by ACTH or an ACTH-related peptide. Therefore, the aldosterone and prolactin responses to metoclopramide have been studied in 10 patients with severe congestive heart failure (NYHA Class III or IV) after 6 months of captopril treatment, before and 11 h after pretreatment with dexamethasone. 7 placebo-treated patients served as double-blind controls. In captopril-treated patients, the supine aldosterone levels exceeded the normal range and were as high as in placebo-treated patients. The responsiveness of aldosterone and prolactin to metoclopramide was not influenced by captopril. Only in the placebo group were the aldosterone levels decreased by dexamethasone. Captopril increased plasma renin activity and serum potassium, and decreased supine epinephrine and norepinephrine and serum sodium. Thus, previous reports of inappropriately high aldosterone levels after long-term captopril treatment were confirmed in patients with severe congestive heart failure. It is concluded that increased aldosterone is due neither to a decrease in endogenous dopaminergic inhibition nor to dexamethasone-suppressible stimulation of aldosterone secretion.

Characterization of different deoxyribonucleases in human lymphocytes

Four groups of deoxyribonuclease activities from human lymphocytes have been characterized by deoxyribonuclease assay in DNA-containing polyacrylamide gels following their separation by disc-electrophoresis. All activities hydrolyse DNA endonucleolytically. One neutral deoxyribonuclease found in the cytoplasmic fraction prefers native or UV-irradiated DNA over denatured DNA as substrate and is a 5'-monoester former. Two groups of acid deoxyribonuclease activities are detectable in the nuclear fraction. Both are 3'-monoester formers. One is as well active with denatured DNA as with native DNA, the other one shows the same activity with native and UV-irradiated DNA but lower activity with denatured DNA. An alkaline deoxyribonuclease activity, also localized in the nucleus, is a 5'-monoester former, and prefers denatured or UV-irradiated DNA as substrate.