Significant aortic regurgitation after transfemoral aortic valve implantation: patients' gender as independent risk factor

AIM

Significant aortic regurgitation (AR) has been reported in 20% of patients undergoing transfemoral aortic valve implantation (TAVI) and has been associated with increased mortality. Depending on the population included and the type of implanted prosthesis, several anatomical and procedural factors have been linked with increased risk of post-TAVI AR. While the impact of patients' gender on this complication, is still contradictory. We sought to assess the impact of patients' gender on the risk of significant AR after TAVI.

METHODS

We included 323 consecutive patients (136 men) who underwent transfemoral implantation of either self-expandable or balloon-expandable prostheses for treatment of symptomatic aortic stenosis.

RESULTS

After TAVI 52 patients (16.1%) had AR grade ≥ 2/4 as evaluated by angiography. They were more frequently male (59.6% vs. 40.4%, P = 0.005), received self-expandable (94.2% vs. 63.5%, P < 0.001) and bigger size prostheses (28 ± 1.9 vs. 27.3 ± 2.1 mm, P = 0.028) and had reduced left ventricular ejection fraction (45.3% ± 14.2% vs. 51.2% ± 13%, P = 0.003) compared to patients with AR grade < 2/4 (N. = 271). In multivariate analysis, men (OR 2.13 [95% CI, 1.08-4.18]) and prosthesis type (OR 13.17 [95% CI, 3.24-57.97]) were identified as independent predictors of AR grade ≥ 2/4.

CONCLUSION

Alongside with the implantation of self-expandable aortic prosthesis, male gender independently increases the risk of significant AR in patients undergoing TAVI. The question if this finding is related to gender biology itself or to gender-related aggregation of subtle anatomic characteristics needs further investigations.

A randomized trial comparing phosphorylcholine-coated stenting with balloon angioplasty as well as abciximab with placebo for restenosis reduction in small coronary arteries

OBJECTIVE

The objective of this randomized trial was to assess the antirestenotic effects of phosphorylcholine (PC)-coated stents as well as of abciximab in small coronary arteries when compared with percutaneous transluminal coronary angioplasty (PTCA) and placebo respectively.

BACKGROUND

Stent coating with PC has been shown to reduce protein absorption and platelet activation which may reduce the risk of restenosis. Furthermore, on the basis of nondedicated studies abciximab is believed to reduce the risk of restenosis after coronary interventions.

METHODS

A total of 502 patients with lesions situated in small coronary arteries (vessel diameter </=2.5 mm) were randomly assigned to be treated with either PC-coated stents (n = 253) or PTCA (n = 249) and with either abciximab (n = 251) or placebo (n = 251) with the use of a 2 x 2 factorial design. All patients were pretreated with 600 mg clopidogrel. The primary end-point was the incidence of angiographic restenosis (>/=50% diameter stenosis) at follow-up; death or myocardial infarction, and target vessel revascularization (TVR), were assessed as secondary end-points.

RESULTS

Angiographic restenosis did not differ between patients treated with PC-coated stents or with PTCA (39.0% vs. 34.2%; P = 0.30) and between patients receiving abciximab or placebo (39.3% vs. 34.3%; P = 0.29). Similarly, the need for TVR at 1-year follow-up did not differ between patients receiving PC-coated stents or PTCA (20.2% vs. 20.5%; P = 0.98) as well as between patients treated with abciximab or placebo (18.7% vs. 21.9%; P = 0.44).

CONCLUSIONS

PC-coated stents and abciximab failed to reduce the incidence of angiographic restenosis after percutaneous coronary intervention of small coronary arteries. These data strengthen the belief that future studies on prevention of restenosis in small coronary arteries should focus on drug-eluting stents.

Incidence of thrombotic occlusion and major adverse cardiac events between two and four weeks after coronary stent placement: analysis of 5,678 patients with a four-week ticlopidine regimen

OBJECTIVES

We attempted to make a comprehensive assessment of the risk of stent failure (death, myocardial infarction or angiographically documented occlusion), differentiating early (first and second weeks) and late (third and fourth weeks) events.

BACKGROUND

The risk of stent failure decreases rapidly within the first week. It has been suggested that the risk rate for late events is close to 0% and that the thienopyridine regimen (ticlopidine or clopidogrel) could be safely reduced from four to two weeks, minimizing the risk of hematological complications.

METHODS

We analyzed 5,678 patients with successful coronary stent placement and a four-week ticlopidine regimen.

RESULTS

The rate of stent failure was 2.5% at four weeks, with 112 early (2.0%) and 30 late events (0.5%). Multivariate analysis identified different risk factors for early versus late events. While variables on stenosis severity and procedural results that can be influenced by the operator were identified as independent risk factors for early events (percent stenosis before and after the procedure, residual dissection, length of stented segment), more clinical variables were associated with late events (age, reduced left ventricular function, systemic hypertension as a protective factor). The late-event rate was <0.1% in the absence of these factors, but it was 2.5% with all three risk factors present.

CONCLUSIONS

The risk of late stent failure is low with a four-week ticlopidine regimen. However, high-risk subgroups have a risk of 2.5%. As this rate is presumably higher if thienopyridines are discontinued after two weeks, these data suggest that a risk stratification to a two- or four-week regimen is preferable to a general reduction.

Sustained benefit over four years from an initial combined antiplatelet regimen after coronary stent placement in the ISAR trial. Intracoronary Stenting and Antithrombotic Regimen

Combined antiplatelet therapy after coronary stent placement is superior to anticoagulation with respect to early outcome. It is unclear if this benefit is maintained during long-term follow-up. This study reports on the 4-year clinical outcome of patients randomized in the Intracoronary Stenting and Antithrombotic Regimen trial. In the Intracoronary Stenting and Antithrombotic Regimen trial, 517 patients were randomized after successful placement of Palmaz-Schatz stents: 257 to aspirin and ticlopidine, and 260 to aspirin and phenprocoumon. Ticlopidine and phenprocoumon were given for 4 weeks. At 30 days, patients with ticlopidine had significantly fewer adverse cardiac events (1.6% vs 6.2%; p = 0.007), nonfatal myocardial infarction (0.8% vs 3.5%; p = 0.034), and target vessel revascularization procedures (1.2% vs 5.4%; p = 0.007). At 4 years, rates for any adverse cardiac events were 22.6% versus 28.5% (p = 0.078), for nonfatal myocardial infarction 0.9% versus 5.8% (p = 0.003), and for target vessel revascularization 18.3% versus 22.7% (p = 0.21). The absolute difference in event rates (4.6% after 30 days) was maintained after 4 years (5.9%). Event rates beyond day 30 were not significantly different (21.1% vs 22.5%; p = 0.78), nor were the rates beyond the first year, which were very low (5.2% vs 3.6%; p = 0.50). This study shows that the benefit of combined antiplatelet therapy evident after 30 days is maintained after 4 years. Independent of the initial regimen, rates of adverse cardiac events are low beyond the first year.

Restenosis after coronary placement of various stent types

Coronary stent implantation is being performed in an increasing number of patients with a wide spectrum of clinical and lesion characteristics. A variety of stent designs are now available and continuous efforts are being made to improve the stent placement procedure. The objective of this study was to perform a comprehensive analysis of the relation between clinical, lesion, and procedural factors, and restenosis after intracoronary stenting in a large and unselected population of patients. A consecutive series of 4,510 patients with coronary stent placement was analyzed. Exclusion criteria were only a failed procedure and an adverse outcome within the first month after the intervention. Follow-up angiography was performed in 80% of patients at 6 months. Clinical, lesion, and procedural data from all 3,370 patients (4,229 stented lesions) with follow-up angiography were analyzed in a logistic regression model for restenosis (> or =50% diameter stenosis). Clinical factors contributed to the predictive power of the model much less than lesion and procedural factors. The strongest risk factor for restenosis was a small vessel size, with a 79% increase in the risk for a vessel of 2.7 mm versus a vessel of 3.4 mm in diameter. Stent design was the second strongest factor; the incidence of restenosis ranged from 20.0% to 50.3% depending on the stent type implanted. In conclusion, this study demonstrates the predominant role of lesion and procedural factors in determining the occurrence of restenosis after coronary stent placement. Among these factors, stent design appears to play a particularly important role in the hyperplastic response of the vessel wall.

Coronary stenting plus platelet glycoprotein IIb/IIIa blockade compared with tissue plasminogen activator in acute myocardial infarction. Stent versus Thrombolysis for Occluded Coronary Arteries in Patients with Acute Myocardial Infarction Study Investigators

BACKGROUND

Prevention of myocardial damage is the main goal of all reperfusion therapies in patients with acute myocardial infarction. The relative efficacy of various reperfusion strategies is under intensive investigation. We assessed whether coronary stenting combined with the blockade of platelet glycoprotein IIb/IIIa receptors produces a greater degree of myocardial salvage than fibrinolysis with an accelerated infusion of alteplase, a tissue plasminogen activator, in patients with acute myocardial infarction.

METHODS

A total of 140 patients were enrolled in the randomized trial; 71 were assigned to receive a stent plus abciximab, and 69 to receive intravenous alteplase. The primary end point was the degree of myocardial salvage, determined by means of serial scintigraphic studies with technetium Tc 99m sestamibi. The secondary end point was a composite of death, reinfarction, and stroke within six months after randomization.

RESULTS

In the group that received a stent plus abciximab, the median size of the final infarct was 14.3 percent of the left ventricle (25th and 75th percentiles, 6.8 and 24.5 percent), as compared with a median of 19.4 percent (25th and 75th percentiles, 7.9 and 34.2 percent) in the alteplase group (P=0.02). This difference was due to the larger salvage index (the percentage of the left ventricle that was salvaged, divided by the percentage that was compromised by the initial perfusion defect) in the stent group: 0.57 (25th and 75th percentiles, 0.35 and 0.69), as compared with 0.26 (25th and 75th percentiles, 0.09 and 0.61; P<0.001). The cumulative incidence of death, reinfarction, or stroke at six months was lower in the stent group than in the alteplase group (8.5 vs. 23.2 percent. P=0.02; relative risk, 0.34; 95 percent confidence interval, 0.13 to 0.88).

CONCLUSIONS

In patients with acute myocardial infarction, coronary stenting plus abciximab leads to a greater degree of myocardial salvage and a better clinical outcome than does fibrinolysis with a tissue plasminogen activator.

Influence of stent design on 1-year outcome after coronary stent placement: a randomized comparison of five stent types in 1,147 unselected patients

The objective of this randomized trial was to assess whether differences in stent design are translated in different clinical outcomes in patients undergoing coronary stent placement. This multicenter randomized trial included 1,147 patients who were randomly assigned to receive one of five types of stainless steel stents: Inflow, MULTI-LINK, NIR, Palmaz-Schatz, and PURA-A stent. Primary endpoint of the study was event-free survival at 1 year. Event-free survival at 1 year was significantly different between the groups (P = 0.014), ranging from 69.4% to 82.4%. Similarly, freedom from myocardial infarction was also significantly different (P = 0.022), with values between 88.2% and 95.2%. Diameter stenosis at 6 months varied from 38.1% +/- 25.0% to 45.6% +/- 27.7% (P = 0. 046), late lumen loss ranged from 1.01 +/- 0.70 mm to 1.20 +/- 0.82 mm (P = 0.085), and the incidence of restenosis varied between 25.3% and 35.9% (P = 0.145). Thus, stent design has a significant impact on the long-term results after coronary stent placement.

Increased risk of restenosis after placement of gold-coated stents: results of a randomized trial comparing gold-coated with uncoated steel stents in patients with coronary artery disease

BACKGROUND

Gold is a highly biocompatible material. Experimental evidence suggests that coating the stent with a gold layer may have a beneficial influence. In this randomized trial, we assessed whether gold-coated stents were associated with a better clinical and angiographic outcome after coronary placement.

METHODS AND RESULTS

Patients with symptomatic coronary artery disease were randomly assigned to receive either a gold-coated Inflow stent (n = 367) or an uncoated Inflow stainless steel stent (n = 364) of identical design. Follow-up angiography was routinely performed at 6 months. The primary end point of the study was the occurrence of any adverse clinical event (death, myocardial infarction, or target-vessel revascularization) during the first year after stenting. At 30 days, there was no significant difference in the combined incidence of adverse events, with 7.9% in the gold-stent group versus 5.8% in the steel-stent group (P = 0.25). The incidence of angiographic restenosis (> or =50% diameter stenosis) was 49.7% in the gold-stent group and 38.1% in the steel-stent group (P = 0.003). One-year survival free of myocardial infarction was 88.6% in the gold-stent group and 91.8% in the steel-stent group (P = 0.14). One-year event-free survival was significantly less favorable in the gold-stent group (62.9% versus 73.9% in the steel-stent group; P = 0.001).

CONCLUSIONS

Coating steel stents with gold had no significant influence on the thrombotic events observed during the first 30 days after the intervention. However, gold-coated stents were associated with a considerable increase in the risk of restenosis over the first year after stenting.

Primary intracoronary stenting in acute myocardial infarction: long-term clinical and angiographic follow-up and risk factor analysis

BACKGROUND

Coronary stent placement may be an effective primary intervention in acute myocardial infarction. Recently published or reported data indicate that primary stenting may be superior to primary plain balloon angioplasty in this setting. The aim of this study was to analyze the long-term clinical and angiographic follow-up of patients treated with primary intracoronary stenting and to identify the predictive factors of an adverse outcome.

METHODS

The study population was composed of 519 consecutive patients with acute myocardial infarction (43 in cardiogenic shock) and attempted primary stent implantation. Adverse clinical events such as death, recurrent infarction, and target vessel revascularization were recorded. Six-month follow-up angiography was performed in 78.2% of the eligible patients, and coronary dimensions were assessed with an automated quantitative system.

RESULTS

Procedural success was achieved in 500 patients (96.3%). The incidence of reocclusion was 3.2%. Thirty-day mortality rate was 5. 4% (2.5% in patients without shock); adverse clinical events were encountered in 10.4% of the patients. Independent risk factors for an adverse outcome were longer time to treatment, Killip class, reduced left ventricular function, overlapping stents, and residual dissection. The incidence of angiographic restenosis was 30.6%. One-year survival rate was 89.0%; 86.5% of the patients did not have a myocardial infarction and 71.7% did not have any major adverse event.

CONCLUSIONS

Primary intracoronary stenting in patients with acute myocardial infarction is associated with a favorable early and long-term outcome. This is the result of low reocclusion and restenosis rates achieved by stenting.

Influence of balloon pressure during stent placement in native coronary arteries on early and late angiographic and clinical outcome: A randomized evaluation of high-pressure inflation

BACKGROUND

High-pressure dilatation is considered a better stent placement strategy, but this has not yet been proved by appropriately designed studies. The objective of this randomized trial was to assess the role of high-pressure dilatation in the early and late outcome of patients undergoing coronary stent placement.

METHODS AND RESULTS

Consecutive patients with coronary stent placement were randomly assigned to high- (15 to 20 atm, 468 patients) or low- (8 to 13 atm, 466 patients) balloon-pressure dilatation. The primary end point of the study was the event-free survival at 1 year. Secondary end points were the incidence of stent thrombosis at 30 days and angiographic restenosis (>/=50% diameter stenosis) at 6 months. The incidence of stent thrombosis was 1.7% in the high-pressure and 1.9% in the low-pressure group (relative risk 0.89; 95% CI 0.30 to 2.56). During the first 30 days, although there was no significant difference in the incidence of Q-wave myocardial infarction, the incidence of non-Q-wave infarction was 6.4% in the high-pressure and 3.4% in the low-pressure group (relative risk 1. 87; 95% CI 1.02 to 3.42). The restenosis rate was 30.4% in the high-pressure and 31.4% in the low-pressure group (relative risk 0. 97; 95% CI 0.75 to 1.26). Event-free survival at 1 year was not significantly different between the groups, with 78.8% in high-pressure patients and 75.5% in patients assigned to low-pressure dilatation (hazard ratio 0.85; 95% CI 0.65 to 1.11).

CONCLUSIONS

The systematic use of high-balloon-pressure inflation (15 to 20 atm) during coronary stent placement is not associated with any significant influence on the 1-year outcome of patients undergoing this intervention.

Diabetes mellitus and the clinical and angiographic outcome after coronary stent placement

OBJECTIVES

The objectives of this study were to analyze the clinical and angiographic outcome of diabetic patients with successful coronary stent placement and to compare these results with those achieved after stenting in nondiabetic patients.

BACKGROUND

The outcome of diabetic patients treated with stent placement due to coronary artery disease has not been assessed comprehensively.

METHODS

This study analyzes a consecutive series of patients with successful stent placement comprising 715 patients with diabetes and 2,839 patients without diabetes. Clinical one year follow-up and angiographic control at 6 months were part of the protocol. Death, myocardial infarction and target lesion revascularization were considered as adverse events. An automated edge detection system was used for the angiographic assessment. The primary clinical endpoint was event-free survival at one year. The primary angiographic endpoint was restenosis rate at 6 months (> or = 50% diameter stenosis).

RESULTS

Event-free survival was significantly lower in diabetic than in nondiabetic patients (73.1 vs. 78.5%, p < 0.001). Survival free of myocardial infarction was also significantly reduced in the diabetic group (89.9 vs. 94.4% in nondiabetics, p < 0.001). The incidence of both restenosis (37.5 vs. 28.3%, p < 0.001) and stent vessel occlusion (5.3 vs. 3.4%, p = 0.037) was significantly higher in diabetic patients. Diabetes was identified as an independent risk factor for adverse clinical events and restenosis in multivariate analyses.

CONCLUSIONS

Patients with diabetes mellitus have a less favorable clinical outcome at one year after successful stent placement as compared to the nondiabetic patients. The clinical follow-up was characterized by a higher incidence of death, myocardial infarction and reinterventions. Diabetic patients also demonstrated an increased risk for restenosis.

A comparative study of activity and dual sensor: activity and minute ventilation pacing responses to ascending and descending stairs

Previous studies with activity-based rate adaptive pacemakers have shown a somewhat paradoxical response when comparing ascending stairs to descending stairs. The objective of this investigation was to measure dual-sensor rate response provided by activity and minute ventilation (MV) compared with activity alone, and with a control group, during ascending and descending stairs. For dual sensor mode, measured mean peak pacing rate with 72 (92) steps per minute was 111 +/- 13 beats/min (124 +/- 14 beats/min) ascending stairs and 81 +/- 7 beats/min (97 +/- 13 beats/min) for descending. For activity mode alone, mean peak pacing rate was 90 +/- 12 beats/min (108 +/- 19 beats/min) ascending stairs and 97 +/- 12 beats/min (123 +/- 17 beats/min) descending. The mean peak control group heart rate ascending stairs for a step rate of 72 (92) steps/min were 116 +/- 11 beats/min (127 +/- 14 beats/min) ascending stairs and for descending 89 +/- 12 beats/min (95 +/- 11 beats/min). While for dual sensor controlled pacing there was a significant difference for ascending and descending stairs at both step rates, there was no difference between going upstairs and downstairs for activity mode alone. Rates with dual sensor did not significantly differ from respective rates of the control group. The mean correlation coefficient between MV and paced rate was 0.85. Pacing heart rates delivered by the dual sensor mode were appropriate for ascending and descending stairs. In contrast to activity mode alone, the peak heart rates for dual sensor mode are higher during ascending than during descending stairs.

Intracoronary stenting and risk for major adverse cardiac events during the first month

BACKGROUND

Our rationale for this study was to analyze the risk for procedural failure of attempted stenting and the risk for major adverse cardiac events (MACE) after success and to develop a risk stratification protocol for successful procedures.

METHODS AND RESULTS

Stenting was attempted in 2894 procedures during the 5-year study period (success in 98.3% of 3815 lesions). After failure, the MACE rate was 42.6%. The risk for failure was higher for lesions in the left circumflex coronary artery or in venous bypass grafts and after an acute occlusion before stenting; it increased with stenosis length or grade and decreased with vessel size and growing institutional experience in stenting. After success, death occurred in 0.8%, death or myocardial infarction in 2.0%, and any MACE in 3.6%. Independent risk factors for MACE were older age, diabetes, acute myocardial infarction, unstable angina, impaired left ventricular function, residual dissections, stent overlap, longer stented segments, and a postprocedural regimen without ticlopidine. Procedural factors were substantially stronger predictors than operator-independent variables available before procedures. Overall, the risk declined after the first 3 days. Two major factors exhibited time-dependent variations of their influence: while residual dissections were the dominant risk factor within the first 3 days with a reduction after that, no protective effect of ticlopidine could be identified before day 3. From these results, we derived a risk stratification protocol for individual procedures.

CONCLUSIONS

These results underscore the importance of optimal angiographic results and the need for antiplatelet regimens with immediate onset. Our risk stratification protocol may guide individual postprocedural care and allow us to compare risk profiles of different study populations and to devise quality control programs for stenting.