Predictive factors for ischemic target vessel revascularization in the Prevention of Restenosis with Tranilast and its Outcomes (PRESTO) trial

A risk score for predicting in-stent restenosis in patients with premature acute myocardial infarction undergoing percutaneous coronary intervention with drug-eluting stent

Background

This study aimed at developing and validating a risk score to predict in-stent restenosis (ISR) in patients with premature acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) with drug-eluting stent (DES).

Methods

This was a two-center retrospective study. A total of 2185 patients firstly diagnosed with premature AMI (age ≥18 years and <55 years in men, <65 years in women) from Xinjiang cohort were retrospectively analyzed. After filtering by exclusion criteria, patients were randomly divided into training cohort (n = 434) and internal validation cohort (n = 186) at a 7:3 ratio. Several candidate variables associated with ISR in the training cohort were assessed by the least absolute shrinkage and selection operator and logistic regression analysis. The ISR risk nomogram score based on the superior predictors was finally developed, and then validated in the internal validation cohort and in an independent Chengdu external validation cohort (n = 192). The higher total nomogram score, the greater the ISR risk.

Results

The eight variables in the final risk nomogram score, cardiovascular-kidney-metabolic (CKM) score included age, diabetes mellitus (DM), body mass index (BMI), systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDLC), estimated glomerular filtration rate (eGFR), stent in left anterior descending coronary artery, minimum stent diameter <3 mm. The areas under the curve (AUC) and C-statistics [training cohort: 0.834 (95%CI: 0.787 to 0.882); internal validation cohort: 0.852 (95%CI: 0.784 to 0.921); Chengdu external validation cohort: 0.787 (95%CI: 0.692 to 0.882), respectively)] demonstrated the good discrimination of the CKM score. The Hosmer-Lemeshow test (χ2 = 7.86, P = 0.448; χ2 = 5.17, P = 0.740; χ2 = 6.35, P = 0.608, respectively) and the calibration curve confirmed the good calibration of the CKM score. Decision curve analysis (DCA) testified the clinical net benefit of the CKM score in the training and validation cohort.

Conclusion

This study provided a well-developed and validated risk nomogram score, the CKM score to predict ISR in patients with premature AMI undergoing PCI with DES. Given that these variables are readily available and practical, the CKM score should be widely adopted for individualized assessment and management of premature AMI.

Stent-specific fat attenuation index is associated with target vessel revascularization after PCI

OBJECTIVES

To explore the clinical relevance of stent-specific perivascular fat attenuation index (FAI) in patients with stent implantation.

METHODS

A total of 162 consecutive patients who underwent coronary computed tomography angiography (CCTA) following stent implantation were retrospectively included. The stent-specific FAI at 2 cm adjacent to the stent edge was calculated. The endpoints were defined as target vessel revascularization (TVR) on the stented vessel after CCTA and readmission times due to chest pain after stent implantation. Binary logistic regression analysis for TVR and ordinal regression models were conducted to identify readmission times (0, 1, and ≥ 2) with generalized estimating equations on a per-stent basis.

RESULTS

On a per-stent basis, 9 stents (4.5%) experienced TVR after PCI at a median 30 months' follow-up duration. Stent-specific FAI differed significantly among subgroups of patients with stent implantation and different readmission times (p = 0.002); patients with at least one readmission had higher stent-specific FAI than those without readmission (p < 0.001). Bifurcated stents (odds ratio [OR]: 11.192, p = 0.001) and stent-specific FAI (OR: 1.189, p = 0.04) were independently associated with TVR. With no readmission as a reference, stent-specific FAI (OR: 0.984, p = 0.007) was an independent predictor for hospital readmission times ≥ 2 (p = 0.003).

CONCLUSION

Non-invasive stent-specific FAI derived from CCTA was found to be associated with TVR, which was a promising imaging marker for functional assessment in patients who underwent stent implantation.

CLINICAL RELEVANCE STATEMENT

Noninvasive fat attenuation index adjacent to the stents edge derived from CCTA, an imaging marker reflecting the presence of inflammation acting on the neointimal tissue at the sites of coronary stenting, might be relevant clinically with target vessel revascularization.

KEY POINTS

• Non-invasive stent-specific FAI derived from CCTA was associated with TVR (OR: 1.189 [95% CI: 1.007-1.043], p = 0.04) in patients who underwent stent implantation. • Stent-specific FAI significantly differed among a subgroup of patients with chest pain after stent implantation and with different readmission times (p = 0.002); the patients with at least one readmission had higher stent-specific FAI than those without readmission (p < 0.001). • Non-invasive stent-specific FAI derived from CCTA could be used as an imaging maker for the functional assessment of patients following stent implantation.

The Impact of Oxygen Pulse and Its Curve Patterns on Male Patients with Heart Failure, Chronic Obstructive Pulmonary Disease, and Healthy Controls—Ejection Fractions, Related Factors and Outcomes

Oxygen pulse (O₂P) is a function of stroke volume and cellular oxygen extraction and O₂P curve pattern (O₂PCP) can provide continuous measurements of O₂P. However, measurements of these two components are difficult during incremental maximum exercise. As cardiac function is evaluated using ejection fraction (EF) according to the guidelines and EF can be obtained using first-pass radionuclide ventriculography, the aim of this study was to investigate associations of O₂P%predicted and O₂PCP with EF in patients with heart failure with reduced or mildly reduced ejection fraction (HFrEF/HFmrEF) and chronic obstructive pulmonary disease (COPD), and also in normal controls. This was a prospective observational cross-sectional study. Correlations of resting left ventricular EF, dynamic right and left ventricular EFs and outcomes with O₂P% and O₂PCP across the three participant groups were analyzed. A total of 237 male subjects were screened and 90 were enrolled (27 with HFrEF/HFmrEF, 30 with COPD and 33 normal controls). O₂P% and the proportions of the three types of O₂PCP were similar across the three groups. O₂P% reflected dynamic right and left ventricular EFs in the control and HFrEF/HFmrEF groups, but did not reflect resting left ventricular EF in all participants. O₂PCP did not reflect resting or dynamic ventricular EFs in any of the subjects. A decrease in O₂PCP was significantly related to nonfatal cardiac events in the HFrEF/HFmrEF group (log rank test, p = 0.01), whereas O₂P% and O₂PCP did not predict severe acute exacerbations of COPD. The findings of this study may clarify the utility of O₂P and O₂PCP, and may contribute to the currently used interpretation algorithm and the strategy for managing patients, especially those with HFrEF/HFmrEF. (Trial registration number NCT05189301.)

Development and validation of a risk prediction nomogram for in-stent restenosis in patients undergoing percutaneous coronary intervention

Background

This study aimed to develop and validate a nomogram to predict probability of in-stent restenosis (ISR) in patients undergoing percutaneous coronary intervention (PCI).

Methods

Patients undergoing PCI with drug-eluting stents between July 2009 and August 2011 were retrieved from a cohort study in a high-volume PCI center, and further randomly assigned to training and validation sets. The least absolute shrinkage and selection operator (LASSO) regression model was used to screen out significant features for construction of nomogram. Multivariable logistic regression analysis was applied to build a nomogram-based predicting model incorporating the variables selected in the LASSO regression model. The area under the curve (AUC) of the receiver operating characteristics (ROC), calibration plot and decision curve analysis (DCA) were performed to estimate the discrimination, calibration and utility of the nomogram model respectively.

Results

A total of 463 patients with DES implantation were enrolled and randomized in the development and validation sets. The predication nomogram was constructed with five risk factors including prior PCI, hyperglycemia, stents in left anterior descending artery (LAD), stent type, and absence of clopidogrel, which proved reliable for quantifying risks of ISR for patients with stent implantation. The AUC of development and validation set were 0.706 and 0.662, respectively, indicating that the prediction model displayed moderate discrimination capacity to predict restenosis. The high quality of calibration plots in both datasets demonstrated strong concordance performance of the nomogram model. Moreover, DCA showed that the nomogram was clinically useful when intervention was decided at the possibility threshold of 9%, indicating good utility for clinical decision-making.

Conclusions

The individualized prediction nomogram incorporating 5 commonly clinical and angiographic characteristics for patients undergoing PCI can be conveniently used to facilitate early identification and improved screening of patients at higher risk of ISR.

An analysis of factors related to the development of in-stent restenosis after percutaneous coronary intervention

To investigate the relationship between life style, medication adherence and the development of in-stent restenosis after percutaneous coronary intervention.A total of 230 patients with coronary heart disease were recruited and investigated with semi-quantitative food frequency questionnaire, international physical activity questionnaire, screening tool for psychological and Morisky questionnarie. Logistic regression was used for statistical analysis.Logistic regression analysis revealed that there was positive correlation between Morisky score (OR = 1.503), anger (OR = 1.135) and restenosis; and there was negative correlation between physical activity (OR = 0.346), folate intake (OR = 0.926), Vitamin C ingestion (OR = 0.881) and restenosis.The lifestyle and medication adherence of patients after percutaneous coronary intervention are predictors of restenosis, suggesting that it is necessary to strength intervention program to reduce restenosis.

Hemorheologic Alterations in Patients with Type 2 Diabetes Mellitus Presented with an Acute Myocardial Infarction

BACKGROUND

Hemorheologic indices are known to be related to vascular complications in variable clinical settings. However, little is known about the associations between hemorheologic parameters and acute myocardial infarction (AMI) in type 2 diabetes mellitus (T2DM). The purpose of this study was to demonstrate the changes of hemorheologic environment inside of blood using hemorheologic parameters, especially the elongation index (EI) and critical shear stress (CSS) in diabetics with versus without AMI.

METHODS

A total of 195 patients with T2DM were enrolled. Patients were divided into the study group with AMI (AMI+, n=77) and control group (AMI-, n=118) who had no history of coronary artery disease. Hemorheologic parameters such as EI and CSS were measured and compared between the two groups.

RESULTS

The EI was lower (30.44%±1.77% in AMI+ and 31.47%±1.48% in AMI-, P<0.001) but the level of CSS was higher (316.13±108.20 mPa in AMI+ and 286.80±85.34 mPa in AMI-, P=0.040) in the AMI+. The CSS was significantly related to the erythrocyte sedimentation rate (R²=0.497, P<0.001) and use of dipeptidyl peptidase-4 inhibitors (R²=0.574, P=0.048).

CONCLUSION

Diabetics with AMI resulted in adverse hemorheologic changes with lower EI and higher CSS compared to diabetic subjects without AMI. Evaluation of the hemorheologic parameters may provide valuable supplementary information for managing patients with AMI and T2DM.

Five-year clinical outcomes of drug-eluting stents according to on-label and off-label use

BACKGROUND/AIMS

To compare the clinical outcomes of 'on-label' and 'off-label' drug-eluting stents (DESs) over a 5-year follow-up period.

METHODS

A total of 929 patients that underwent percutaneous coronary intervention with DESs were enrolled. Patients were divided into two groups according to on-label (n = 449) and off-label (n = 480) indications. Off-label use was defined as implantation of DESs for acute myocardial infarction (MI), very small vessel, a long stenotic lesion, chronic total occlusion, a bifurcation lesion, an ostial lesion, left main coronary artery disease, multivessel disease, a saphenous vein graft lesion, and a lesion with thrombus. Endpoints were composite of major adverse cardiac events (MACEs), which included all-cause death, ischemic-driven target vessel revascularization (Id-TVR), MI, and stent thrombosis (ST). Clinical outcomes in the two groups were compared for up to 5 years postimplantation.

RESULTS

At 1 year postimplantation, the off-label group had higher incidences of total MACEs (8.2% vs. 3.7%, p = 0.005), Id-TVR (5.0% vs. 1.6%, p = 0.004), and ST (1.7% vs. 0.3%, p = 0.042), and at 5 years postimplantation, the off-label group continued to have higher incidences of total MACEs (17.5% vs. 9.4%, p < 0.001), Id-TVR (13.1% vs. 5.8%, p = 0.024), and ST (2.1% vs. 0.3%, p = 0.021). Multivessel disease and diabetes were found to be independent risk factors of MACE in patients with an off-label indication.

CONCLUSIONS

Patients treated with an on-label DES had better long-term clinical outcomes than those treated with an off-label DES.

Predicting target vessel revascularization in older patients undergoing percutaneous coronary intervention in the drug-eluting stent era

BACKGROUND

The contemporary need for repeat revascularization in older patients after percutaneous coronary intervention (PCI) has not been well studied. Understanding repeat revascularization risk in this population may inform treatment decisions.

METHODS

We analyzed patients ≥65 years old undergoing native-vessel PCI of de novo lesions from 2005 to 2009 discharged alive using linked CathPCI Registry and Medicare data. Repeat PCIs within 1 year of index procedure were identified by claims data and linked back to CathPCI Registry to identify target vessel revascularization (TVR). Surgical revascularization and PCIs not back linked to CathPCI Registry were excluded from main analyses but included in sensitivity analyses. Independent predictors of TVR after drug-eluting stent (DES) or bare-metal stent (BMS) implantation were identified by multivariable logistic regression.

RESULTS

Among 343,173 PCI procedures, DES was used in 76.5% (n = 262,496). One-year TVR ranged from 3.3% (overall) to 7.1% (sensitivity analysis). Precatheterization and additional procedure-related TVR risk models were developed in BMS (c-indices 0.54, 0.60) and DES (c-indices 0.57, 0.60) populations. Models were well calibrated and performed similarly in important patient subgroups (female, diabetic, and older [≥75 years]). The use of DES reduced predicted TVR rates in high-risk older patients by 35.5% relative to BMS (from 6.2% to 4.0%). Among low-risk patients, the number needed to treat with DES to prevent 1 TVR was 63-112; among high-risk patients, this dropped to 28-46.

CONCLUSIONS

In contemporary clinical practice, native-vessel TVR among older patients occurs infrequently. Our prediction model identifies patients at low versus high TVR risk and may inform clinical decision making.

Impact of myocardial bridge on clinical outcome after coronary stent placement

Most intravascular ultrasound (IVUS)-identifiable myocardial bridges (MBs) were not appreciated angiographically, especially when they occurred adjacent to fixed proximal obstructive disease. The impact of MB stent placement on clinical outcome was determined in 317 consecutive patients with obstructive left anterior descending coronary artery lesions undergoing coronary stent placement. In these patients, IVUS identified 70 MBs, defined as a segment of coronary artery with both systolic compression and perivascular echolucent muscle. IVUS showed that the stent extended into the MB segment beyond the obstructive lesion in 24 patients (34%; MB stent group), although significant plaque was not observed within any MB segment. In the remaining 46 patients, the left anterior descending artery stent was implanted in only the obstructive lesion, avoiding the distal MB segment (non-MB stent group). Minimum stent area was significantly smaller in the MB stent group than non-MB stent group (4.8 +/- 1.1 vs 5.8 +/- 1.8 mm(2); p = 0.02). Rates of target-lesion revascularization, target-vessel revascularization, and composite end point (death/myocardial infarction/target-lesion revascularization/target-vessel revascularization, evaluated at a mean follow-up of 358 +/- 252 days) were more common in patients with versus without MB stent placement. Specifically, target-lesion revascularization rates were 24% versus 3%, respectively (log-rank p = 0.003). In-stent restenosis occurred within the stented MB segment in 3 of 5 MB stent group patients who required target-lesion revascularization (60%). In conclusion, inadvertent MB stent placement in left anterior descending artery lesions occurred commonly and may have been associated with an increased incidence of late events.

Impact of metabolic syndrome and C-reactive protein on outcome after coronary stenting

Metabolic syndrome (MS) identifies cardiovascular risk; however, there is little information regarding the evolution of patients with MS after stent implantation. The aim of this single-center study is to evaluate the possible association between MS and clinical restenosis, after adjustment for highsensitivity C-reactive protein (hs-CRP) and angiographic predictors of restenosis. In a longitudinal study, 159 patients (89 with and 70 without MS) were studied. Criteria for MS were: elevated blood pressure (systolic >or=130 mmHg, diastolic >or=85 mmHg or drug treatment for hypertension; elevated fasting glucose (>100 mg/dl) or drug treatment for elevated glucose; reduced HDL-cholesterol (<40 mg/dl in men and <50 mg/dl in women) or drug treatment for reduced HDL-cholesterol; elevated triglycerides (>or=150 mg/dl) or drug treatment for elevated triglycerides; and obesity (body mass index >28.8 kg/m2). The primary end point was the rate of major adverse clinical events (MACE): cardiovascular death, myocardial infarction, or target lesion revascularization (TLR) during the 12-month follow-up period. The secondary end point was the rate of TLR. MS was neither identified as predictor of MACE [hazard ratio (HR): 0.844; 95% CI: 0.41-1.74; p=0.648], nor TLR (HR: 1.05; 95% CI: 0.44-2.50; p=0.91), even when controlled for hs-CRP levels and angiographic predictors of restenosis. Also, no significant interaction between MS and hs-CRP was found (p=0.135 and p=0.194, for MACE and TLR, respectively). This study shows that patients with MS do not have an additional risk of MACE, even when controlled for angiographic predictors of restenosis and hs-CRP.

Implementing an innovative consent form: the PREDICT experience

BACKGROUND

In the setting of coronary angiography, generic consent forms permit highly variable communication between patients and physicians. Even with the existence of multiple risk models, clinicians have been unable to readily access them and thus provide patients with vague estimations regarding risks of the procedure.

METHODS

We created a web-based vehicle, PREDICT, for embedding patient-specific estimates of risk from validated multivariable models into individualized consent documents at the point-of-care. Beginning August 2006, outpatients undergoing coronary angiography at the Mid America Heart Institute received individualized consent documents generated by PREDICT. In February 2007 this approach was expanded to all patients undergoing coronary angiography within the four Kansas City hospitals of the Saint Luke's Health System. Qualitative research methods were used to identify the implementation challenges and successes with incorporating PREDICT-enhanced consent documents into routine clinical care from multiple perspectives: administration, information systems, nurses, physicians, and patients.

RESULTS

Most clinicians found usefulness in the tool (providing clarity and educational value for patients) and satisfaction with the altered processes of care, although a few cardiologists cited delayed patient flow and excessive patient questions. The responses from administration and patients were uniformly positive. The key barrier was related to informatics.

CONCLUSION

This preliminary experience suggests that successful change in clinical processes and organizational culture can be accomplished through multidisciplinary collaboration. A randomized trial of PREDICT consent, leveraging the accumulated knowledge from this first experience, is needed to further evaluate its impact on medical decision-making, patient compliance, and clinical outcomes.

Restenosis begets restenosis: implications for stent selection

BACKGROUND

Identifying the risk for restenosis is of critical importance in the stent selection process of patients undergoing percutaneous coronary intervention (PCI). Therefore, we sought to determine if a history of clinical recurrence (CR) after PCI increases the risk of CR after treatment of a de novo lesion in another coronary artery.

METHODS

We retrospectively analysed all 12,763 patients who underwent PCI between 1993 and 2004 and selected patients with two or more interventions in two different native vessels. These patients were divided into two groups: patients without CR, and patients with CR after the first PCI. Clinical recurrence was defined as revascular-isation of the target vessel by either PCI or CABG within one year.

RESULTS

A total of 1010 patients with two or more interventions in two different native vessels were identified: 727 patients without and 283 patients with CR after the first PCI. Baseline patient characteristics and conventional risk factors were comparable between the two groups. Patients with a history of CR had a higher risk of CR after a second intervention in a second vessel (OR=3.4, 95% CI=2.3 to 4.9). A total of 112 patients also had a third intervention in a third native vessel: 12 patients with two CR, 30 patients with one CR and 70 patients with no CR after the first two interventions. CR rates in these patients were 50, 17 and 3%, respectively (p<0.001).

CONCLUSION

Patients with a history of CR have a markedly increased risk of developing CR after a second or third PCI in a different coronary artery. Therefore, in the decision-making process on whether to use a bare metal stent or drug-eluting stent, the history of CR is a simple and powerful aid. (Neth Heart J 2008;16:376-81.).

The relation between clinical features, angiographic findings, and the target lesion revascularization rate in patients receiving the endeavor zotarolimus-eluting stent for treatment of native coronary artery disease: an analysis of ENDEAVOR I, ENDEAVOR II, ENDEAVOR II Continued Access Registry, and ENDEAVOR III

The clinical and angiographic factors that predict clinically driven target lesion revascularization (TLR) in patients treated with the zotarolimus-eluting stent (ZES) are not known. Accordingly, the differences between ZES-treated patients who required TLR and ZES-treated patients who did not require TLR were examined in 1,306 patients enrolled in 4 pivotal trials of the Endeavor ZES (Medtronic Vascular, Santa Rosa, CA) for the treatment of symptomatic native coronary artery disease. TLR was performed in 64 patients (4.9%) by 9 months, with most cases (89.1%) occurring after 30 days. ZES-treated patients who required TLR had a greater incidence of 2- or 3-vessel disease (p <0.01), more stents implanted (p = 0.05), and lower device (p = 0.04) and procedure (p <0.01) success rates than ZES-treated patients who did not require TLR. The stents implanted in ZES-treated patients who later required TLR were also longer (p = 0.02) and smaller in diameter (p <0.01). Most angiographic outcomes at 8 months (12 months for ZES-treated patients in ENDEAVOR I) were worse for ZES-treated patients who later required TLR. At 9 months, 10.9% of the ZES-treated patients who required TLR had had myocardial infarctions, compared with 2.2% who did not require TLR (p = 0.001). Multivariate analysis identified older age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.00-1.06), male sex (OR, 1.79; 95% CI, 0.88-3.65), and longer lesion length (OR, 1.03; 95% CI, 0.99-1.07) as risk factors for TLR after ZES implantation (with a C statistic of 0.61, suggesting a modest discriminatory value). These data provide insight into the clinical and angiographic factors that predict TLR at 9 months in ZES-treated patients, making possible the focused surveillance of selected ZES-treated patients who might be at greater risk of TLR.

Geographical Differences in the Rates of Angiographic Restenosis and Ischemia-Driven Target Vessel Revascularization After Percutaneous Coronary Interventions

Many cardiologists consider it reasonable to assume in clinical practice that percutaneous coronary intervention using drug-eluting stents ought to be considered equivalent, if not superior, to bypass surgery. In the absence of a definitive clinical trial to support this view, how should the prudent, cutting-edge cardiologist proceed?

OBJECTIVES

This study assessed the geographical differences in target vessel revascularization (TVR) after percutaneous coronary intervention (PCI) in the Prevention of Restenosis With Tranilast and its Outcomes (PRESTO) trial.

BACKGROUND

An aggressive approach to PCI is more common in the U.S. than in other countries. The impact of this approach on restenosis outcomes has not been studied.

METHODS

Using the PRESTO trial, we compared nine-month ischemic TVR after PCI in U.S.-treated patients (n = 5,026) with rates in other countries (n = 6,458). We defined TVR as repeat intervention for chest pain/positive stress test. Additionally, angiographic restenosis (> or =50% narrowing or > or =50% loss of gain at nine-month follow-up) was compared between U.S. and non-U.S. patients within the prespecified angiographic subset (n = 2,823). Regression models were developed to adjust for clinical and lesion-related characteristics.

RESULTS

Higher rates of TVR (18% vs. 11%), and angiographic restenosis (65% vs. 48%) were observed in patients treated in the U.S. as compared with the other patients (p < 0.01 for both comparisons). Patients treated in the U.S. were more likely to be female, diabetic, not currently smoking, to have unstable angina, and to have a prior PCI. In U.S. patients, lesions tended to be longer, but less likely to be American College of Cardiology/American Heart Association class C. After adjusting for clinical and angiographic variables, PCI in the U.S. was still associated with increased angiographic restenosis and ischemic TVR.

CONCLUSIONS

Angiographic restenosis and ischemia-driven TVR rates were higher in patients treated in the U.S. The difference could only partially be explained by the higher prevalence of measured adverse clinical and angiographic features.

Rapid progression of common femoral artery stenosis leading to development of ischemic foot ulcer following repeated ipsilateral arterial access

Common femoral artery stenosis is well appreciated in patients with peripheral arterial disease, but not described following repeated arterial access. We present a case of progressive right common femoral artery stenosis resulting in resting leg ischemia and ulceration that was temporally related to multiple ipsilateral vascular access procedures for recurrent coronary and peripheral diagnostic and therapeutic procedures. We hypothesize that recurrent arterial injury in a setting of diabetes resulted in progressive critical common femoral artery stenosis.

Clinical restenosis after coronary stent implantation is associated with the heme oxygenase-1 gene promoter polymorphism and the heme oxygenase-1 +99G/C variant

BACKGROUND

Vascular remodeling after percutaneous coronary stent implantation frequently leads to restenosis. Heme oxygenase 1 (HO-1) is involved in the generation of the endogenous antioxidant bilirubin and carbon monoxide, both of which exert antiinflammatory and antiproliferative effects. The aim of the present study was to evaluate the influence of genetic risk factors combined with the conventional risk factors on the development of coronary restenosis after percutaneous coronary intervention (PCI) with stent implantation.

METHODS

The HO-1 gene GT dinucleotide repeat promoter polymorphism and HO-1 +99G/C variant were evaluated in 199 patients with coronary artery disease after coronary stent implantation and control angiography at 6 months after the intervention. Coronary restenosis was confirmed by quantitative angiography.

RESULTS

Carriers of the long allele of the HO-1 gene promoter (>29 repeats) had a significantly higher risk of developing restenosis after PCI than noncarriers [odds ratio (OR)=1.9; 95% confidence interval (95% CI), 1.0-3.4; P=0.04]. Interestingly, the allele longer than 29 repeats conferred a significantly higher risk of developing restenosis (OR=3.4; 95% CI, 1.2-9.1; P=0.017) in nonsmokers than in smokers (OR=2.0; 95% CI, 0.7-5.2; P=0.18).

CONCLUSIONS

The long allele of the HO-1 gene promoter (>29 repeats) polymorphism, which leads to low HO-1 inducibility, may represent an independent prognostic marker for restenosis after PCI and stent implantation. The effect of the >29 repeat allele is attenuated in smokers, who have chronic exogenous CO exposure.