President's page: i2 Summit 2006: one-stop shopping for interventionalists.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to David R Holmes.
Explore the source record for details and available documents.
Previous models for prediction of complications after percutaneous coronary interventions (PCIs) have included in-hospital mortality and major in-hospital complications. In general, these models have excluded elevated cardiac biomarkers as a complication. We sought to determine whether a risk model could predict complications, including biomarker elevation, in patients undergoing nonemergency PCI. We examined the outcomes of nonemergency PCI performed on patients at Mayo Clinic from 2000 to 2003. The primary end point was in-hospital complications of death, myocardial infarction (MI) (Q-wave MI, or post-PCI creatine kinase-MB elevation >or=3 times the upper limit of normal), emergency coronary artery bypass grafting, or stroke. We used the Hosmer-Lemeshow test to demonstrate the adequacy of the model fit, and the c-index for discriminatory ability of the model. Of 2,894 nonemergency PCIs, the end point was noted in 232 (8%). The final prediction model included vein graft intervention (odds ratio [OR] 2.19), angiographic thrombus (OR 2.12), preprocedure stenosis of a minor (OR 1.98) or major (OR 1.62) side branch, and type C lesion (OR 1.48). The model had modest ability to discriminate between event and nonevent patients (c = 0.641). In the 500 bootstrap samples for internal validation, the c-index was 0.642 +/- 0.020, indicating only fair discriminatory ability. The average number of observed events was 232.0 +/- 14.7 compared with 232.1 +/- 2.5 expected events (average difference -0.06 +/- 14.5). In conclusion, the 5 risk variables associated with an increased risk of complications in patients undergoing elective PCI included vein graft intervention, presence of angiographic thrombus, stenosis of a major or minor side branch, and type C lesion; however, the discriminatory ability of the model derived from the variables was only modest.
OBJECTIVES: We sought to determine whether the prescription of evidence-based medications at discharge after successful percutaneous coronary intervention (PCI) can predict long-term clinical outcome. BACKGROUND: The association of standard-of-care drug utilization and long-term mortality and morbidity after PCI is not well studied. METHODS: We performed a retrospective cohort study of successful PCI procedures performed on 7,745 patients between March 1, 1998, and December 31, 2004. Discharge medications were analyzed, and a medication score (MEDS) was developed. A MEDS of 1 was assigned for each of the following medication classes: 1) antiplatelet, 2) lipid-lowering, 3) beta-blocker, and 4) angiotensin-converting enzyme (ACE) inhibitor. The outcomes measured were long-term death, myocardial infarction, and revascularization. RESULTS: Patients with MEDS of 3 to 4 had higher-risk profiles based upon standard clinical and angiographic criteria. Despite this, at a median follow-up of 36 months, patients with a MEDS of 3 or 4 were at lower risk of death than those with a MEDS of 0 or 1 (8.9%, 7.5%, and 13% for MEDS of 4, 3, and 0 to 1, respectively; p = 0.014). After adjustment for covariates, a MEDS of 3 to 4 was associated with significantly lower mortality or myocardial infarction in follow-up than a MEDS of 0 to 1 (hazard ratios of 0.72 and 0.67 for MEDS of 3 and 4, respectively; p < 0.01). There was no association between MEDS and target vessel revascularization. CONCLUSIONS: After successful PCI, the use of multiple evidence-based classes of cardiovascular medications--antiplatelet, lipid-lowering, beta-blockers, and ACE inhibitors--is associated with improved outcome free of death or MI.
Patients with previous percutaneous coronary intervention (PCI) are often excluded from clinical trials. As a result, limited data are available on the long-term outcome of such patients undergoing repeat PCI. In this study, we assessed the impact of previous PCI on outcomes in patients undergoing repeat PCI. We compared the baseline features and outcomes of 7,056 patients without previous PCI (group I) with those of 1,281 patients with previous PCI of the original target lesion (group II) and 1,408 patients with previous PCI of a nontarget lesion (group III) undergoing PCI in the Prevention of Restenosis with Tranilast and its Outcomes (PRESTO) trial. Compared with patients in group I, patients in groups II and III were more likely to have diabetes (25% and 24% vs 21%, p <0.02), previous myocardial infarction (51% and 56% vs 29%, p <0.001), and ostial lesions (10% and 7% vs 5%, p <0.001), and less likely to have, as their indication for PCI, myocardial infarction (2% and 7% vs 17%, p <0.001). At 1 month, major adverse cardiac events, including death, myocardial infarction, and repeat revascularization, were low and similar in all 3 groups. Compared with patients in group I, the risk of major adverse cardiac events at 9 months was significantly increased for patients in groups II (34.1% vs 18.6%, relative risk [RR] 2.03, adjusted RR 1.78, 95% confidence interval 1.58 to 2.01) and III (23.9% vs 18.6%, RR 1.30, adjusted RR 1.16, 95% confidence interval 1.02 to 1.33). The increased risk of major adverse cardiac events was entirely due to higher rates of repeat revascularization. In conclusion, despite similar short-term outcomes, patients with previous PCI undergoing PCI of either target or nontarget lesions had lower event-free survival at 9 months of follow-up.
OBJECTIVES: The aim of this research was to determine the influence of bifurcation lesions on the outcome of patients undergoing percutaneous coronary intervention (PCI) in the recent era. BACKGROUND: The treatment of bifurcation lesions by PCI has been associated with an increased complication rate. Whether recent improvements of interventional practice have translated into improved outcomes in this patient subgroup is unknown. METHODS: The 11,482 patients enrolled in the Prevention of Restenosis with Tranilast and its Outcomes (PRESTO) were stratified according to the presence (n = 1,412) or absence (n = 10,068) of at least one bifurcation lesion treated by PCI. Baseline characteristics and outcome of patients undergoing PCI for bifurcation lesions were compared to those of patients treated for nonbifurcation lesions. RESULTS: Patients treated for bifurcation lesions were less likely to have prior myocardial infarction (MI), prior coronary artery bypass graft surgery, and had a higher proportion of current stable angina (p < 0.01 for all comparisons). Bifurcation lesions involved more frequently the left anterior descending coronary artery and were more complex (angulated, eccentric, ostial, and tortuous) than nonbifurcation lesions. Percutaneous coronary intervention of bifurcation lesions was characterized by less frequent stent implantation (71% vs. 80%); PCI of bifurcation lesions was associated with an increased rate of combined end point death/MI/target vessel revascularization (TVR) at nine months (18% vs. 15%, p = 0.002) because of increased rates of TVR (17% vs. 14%, p < 0.001), whereas death (1%) and MI (1%) were not different between groups. CONCLUSIONS: Percutaneous coronary intervention of bifurcation lesions is associated with higher TVR at follow-up. However, the risk of death, MI, death/MI was similar in patients treated for bifurcation or nonbifurcation lesions.
BACKGROUND: Most studies that are the basis of recommended volume thresholds for percutaneous coronary interventions (PCIs) predate the routine use of stent placement. METHODS AND RESULTS: Data from New York's Percutaneous Coronary Interventions Reporting System in 1998 to 2000 (n=107 713) were used to examine the impact of annual hospital volume and annual operator volume on in-hospital mortality, same-day coronary artery bypass graft (CABG) surgery, and same-stay CABG surgery after adjustment for differences in patients' severity of illness. For a hospital-volume threshold of 400, the odds ratios for low-volume hospitals versus high-volume hospitals were 1.98 (95% CI, 1.17, 3.35) for in-hospital mortality, 2.07 (95% CI, 1.36, 3.15) for same-day CABG surgery, and 1.51 (95% CI, 1.03, 2.21) for same-stay CABG surgery. For an operator-volume threshold of 75, the odds ratios for low-volume versus high-volume operators were 1.65 (95% CI, 1.05, 2.60) for same-day CABG surgery and 1.55 (95% CI, 1.10, 2.18) for same-stay CABG surgery. Operator volume was not significantly associated with mortality. Also, for hospital volumes below 400 and operator volumes below 75, the respective odds of mortality, same-day CABG surgery, and same-stay CABG surgery were 5.92, 4.02, and 3.92 times the odds for hospital volumes of 400 or higher and operator volumes of 75 or higher. CONCLUSIONS: Higher-volume operators and hospitals continue to experience lower risk-adjusted PCI outcome rates.
In-hospital major adverse clinical event (MACE) rates after percutaneous coronary intervention serve as benchmarks of performance. However, accelerated clinical pathways, decreased lengths of stay, and potential delayed effects of percutaneous coronary intervention may result in an underestimation of this traditional measurement of outcome. Records from patients in the first 3 waves of the National Heart, Lung, and Blood Institute's Dynamic Registry (n = 6,676) were reviewed for rates of composite in-hospital MACEs (death, myocardial infarction, and any repeat target vessel revascularization) and postdischarge MACEs (death, myocardial infarction, repeat hospitalization, and repeat target vessel revascularization) through 30 days. Rates for each composite MACE were compared across waves to assess changes over time. Predictors of each MACE category were identified using multivariate analysis. In-hospital MACE decreased significantly (5.4% of wave 1, 4.9% of wave 2, 3.1% of wave 3, p <0.001), whereas stent implantation increased significantly (67.5% of wave 1, 79.1% of wave 2, 86.2% of wave 3, p <0.001). Postdischarge MACE through 30 days remained unchanged (5.1% of wave 1, 5.1% of wave 2, 4.8% of wave 3, p = 0.6). Mean length of stay decreased (2.7 days for wave 1, 2.2 days for wave 3, p <0.001). Disparate clinical, procedural, and angiographic factors were associated with each MACE. Postdischarge MACE rates through 30 days comprise a significant and unchanging fraction of overall procedurally related MACE rates despite improving in-hospital outcomes. Most postdischarge events derive from pathology related to the controlled vessel. A 30-day MACE rate may serve as a more comprehensive measurement of procedural outcome.
Selection of coronary stent length varies from covering only the zone of maximum obstruction to stenting from normal- to normal-appearing vessels. With bare metal stenting, for any given lesion there is a high restenotic risk associated with longer stent length. With drug-eluting stents, the relation between stent length and restenosis has not been evaluated. In the angiographic follow-up cohort of the SIRIUS trial that compared the sirolimus-eluting Bx Velocity stent with the standard Bx Velocity stent (n = 699), we constructed a multiple regression model to predict 8-month percent diameter stenosis using the main effects of lesion length and excess stent length beyond the lesion length and adjusting for known predictors of restenosis. Stent length exceeded lesion length in 94% of lesions overall. Mean difference in length was 8.3 +/- 8.3 mm (mean lesion length 14.6 +/- 5.9 mm, mean stent length 22.9 +/- 9.6 mm). Stented lesion length and excess stent length were associated with absolute increases in percent diameter stenosis per 10 mm of 9.1% (p <0.0001) and 3.6% (p = 0.053) in the bare metal arm and 3.5% (p = 0.047) and 2.1% (p = 0.040) in the sirolimus-eluting stent arm. Although the effects of lesion length and excess stent length on restenosis were markedly decreased with sirolimus-eluting stents (vs bare metal stents), a small restenotic penalty is still paid for excessive stent length. Longer stent-to-lesion length strategies should be used only when a shorter stent is likely to result in incomplete lesion coverage and edge dissection, a strong determinant of stent thrombosis.
Explore the source record for details and available documents.
Myocardial bridging, a congenital coronary anomaly, is a clinical condition with several possible manifestations, and its clinical relevance is debated. This article reviews current knowledge about the anatomy, pathophysiology, clinical relevance, and treatment of myocardial bridging. Myocardial bridging is present when a segment of a major epicardial coronary artery, the 'tunnelled artery', runs intramurally through the myocardium. With each systole, the coronary artery is compressed. Myocardial bridging has been associated with angina, arrhythmia, depressed left ventricular function, myocardial stunning, early death after cardiac transplantation, and sudden death. Evidence indicates that the intima beneath the bridge is protected from atherosclerosis, and the proximal segment is more susceptible to development of atherosclerotic lesions because of haemodynamic disturbances. New techniques (e.g. intravascular ultrasonography and intracoronary Doppler studies) have revealed new characteristics and pathophysiologic processes such as diastolic flow abnormalities. Medical treatment generally includes beta-blockers. Nitrates should be avoided because symptoms may worsen. Intracoronary stents and surgery have been attempted in selected patients. Additional research is needed to define patients in whom myocardial bridging is potentially pathologic, and randomized multicentre long-term follow-up studies are needed to assess the natural history, patient selection, and therapeutic approaches.
Current options for reperfusion therapy in patients admitted to a community hospital without cardiac catheterization facilities include administration of fibrinolytic drugs followed by observation, with referral to angiography driven by symptoms and signs of ischemia; transfer to a tertiary care center for primary percutaneous coronary intervention (PCI); or a strategy of facilitated PCI in which administration of fibrinolytics and platelet glycoprotein IIb/IIIa inhibitors (alone or in combination) is followed by transfer for immediate angiography and PCI if appropriate. We systematically analyzed multiple randomized and nonrandomized trials to review the pathophysiology of reperfusion therapy in acute myocardial infarction to derive insights about the likelihood of success of a strategy of facilitated PCI compared with transfer only or fibrinolysis only. The basis for the recommendations made herein is a hypothetical curve relating the duration of symptoms before reperfusion to reduction in mortality and extent of myocardial salvage. During the first 2 to 3 hours after symptom onset, a striking benefit of reperfusion is present; within this period, time to treatment is critical. Subsequently, a mortality benefit is still present but of decreasing magnitude over time. In this situation, the priority is to open the artery, and time to treatment is less critical. Results of facilitated PCI may depend largely on timing of presentation. If presentation is late after symptom onset (ie, on the "flat" part of the curve), there will be little mortality benefit from earlier patency and patients will be subject to the bleeding risks of fibrinolytic drugs. In contrast, among patients presenting very early (60-90 minutes after symptom onset), outcomes with fibrinolytic therapy alone are excellent, and it will be difficult for any other strategy to result in a significant improvement. But in patients presenting 2 to 3 hours after onset of symptoms, a strategy of facilitated PCI may move patients from the plateau to the descending limb of the curve, with a substantial improvement in myocardial salvage and mortality. Two large ongoing trials may provide definitive answers to these issues.
BACKGROUND: Although segmental or circumferential ablation is effective in eliminating pulmonary vein (PV)-mediated atrial fibrillation (AF), this procedure may be complicated by the occurrence of PV stenosis. METHODS AND RESULTS: To establish the clinical presentation, diagnostic manifestations, and interventional management of PV stenosis, 23 patients with stenosis of 34 veins complicating ablation of AF were evaluated. Each patient became symptomatic 103+/-100 days after undergoing ablation. In 8 veins, the ablation producing the PV stenosis was a repeated procedure for continued AF. Nineteen patients presented with dyspnea on exertion, 7 with dyspnea at rest, 9 with cough, and 6 with chest pain. On multirow spiral computed tomography examination, the narrowest lumen of the affected PVs measured 3+/-2 mm compared with 13+/-3 mm at baseline (P< or =0.001). The relative perfusion of affected lung segments on isotope scans was reduced to 4+/-3% of total perfusion compared with 22+/-10% in unaffected segments. At percutaneous intervention, these veins showed 80+/-13% stenosis, with a mean gradient of 12+/-5 mm Hg. This was significantly reduced to a residual stenosis of 9+/-8% (P< or =0.001) and a residual gradient of 3+/-4 mm Hg (P< or =0.001). Twenty veins were treated with balloon dilatation alone, whereas 14 veins were stented with standard 10-mm-diameter bare-metal stents. Although the symptomatic response was nearly immediate and impressive, 14 patients developed in-stent or in-segment restenosis, requiring repeated interventions in 13. CONCLUSIONS: Percutaneous intervention produces rapid and dramatic symptom relief in patients with highly symptomatic PV stenosis after radiofrequency ablation for AF. Nevertheless, alternative treatment methods will be required to decrease recurrent in-stent or in-segment restenosis.
Multivessel percutaneous coronary intervention (PCI) early after acute myocardial infarction (AMI) is discouraged because of the potential for increased complications. However, with recent advances in PCI, the safety and long-term outcomes of multivessel PCI are unknown. We evaluated the outcomes of multivessel PCI early after AMI (ST-elevation and non-ST-elevation AMI). We identified all patients who had multivessel disease and underwent PCI within 7 days after an AMI from 1997 to 2002. Clinical outcomes were compared between patients who underwent multivessel PCI (n = 239) and patients who underwent treatment of the infarct-related artery alone (n = 1,145). The primary end point was cumulative survival at 6, 12, and 36 months. Secondary end points included a composite of mortality, recurrent infarction, coronary artery bypass graft, or target vessel revascularization at the same time points. There were 138 deaths and 351 occurrences of the composite end point during follow-up. The multivessel PCI group had a significantly higher prevalence of adverse prognostic indicators. Despite this, observed event rates were similar between the multivessel PCI and 1-vessel PCI groups. The Kaplan-Meier estimated 1-year survival was 0.91 (95% confidence interval [CI] 0.87 to 0.95) for the multivessel PCI group and 0.93 (95% CI 0.92 to 0.95) for the 1-vessel PCI group (p = 0.43). Similarly, 1-year survival free of recurrent infarction and target vessel revascularization rates were similar between the 2 groups: multivessel PCI 0.78 (95% CI 0.73 to 0.84) and 1-vessel PCI 0.78 (95% CI 0.75 to 0.81). Multivessel PCI in patients with multivessel coronary artery disease after AMI compared with 1-vessel PCI was not associated with an excess risk of death or of combined death, myocardial infarction, coronary artery bypass graft, or target vessel revascularization.
OBJECTIVES: The aim of the present study was to determine the rates of target vessel revascularization (TVR) and to determine predictors of TVR from clinical and angiographic variables available in the Prevention of Restenosis With Tranilast and its Outcomes (PRESTO) database. BACKGROUND: The rates of TVR after percutaneous revascularization procedures, and its prediction with available clinical and angiographic variables, is less well known. METHODS: We studied nine-month TVR in 11,484 patients enrolled in the PRESTO trial. Clinical, lesion-related, and procedural characteristics were analyzed in a logistic regression model. Study data were divided at random into an 80% training set on which the models were developed and a 20% hold-out set on which the model properties were evaluated. RESULTS: A total of 14% (n = 1,609) had ischemic TVR. Clinical variables with increased risk for TVR included younger age; hypertension; diabetes mellitus; nonsmokers; unstable angina; previous coronary artery bypass grafting; peripheral vascular disease; procedure- and lesion-related such as ostial location, multilesion angioplasty, location in the left anterior descending artery, length > or =20 mm, in-stent restenosis at baseline, and use of rotablator. There was significant increase in the risk of ischemic TVR at U.S. treatment sites. Smoking and stent placement were associated with lower risk of ischemic TVR. The mean area (+/- SD) under the receiver-operating characteristic curve of the bootstrap samples was 0.66, indicating a modest ability of the model to discriminate patients who needed TVR on follow-up. CONCLUSIONS: Despite being the largest prospective trial designed to test restenosis, the discriminatory ability of the clinical and angiographic variables to predict TVR is modest.
OBJECTIVES: The purpose of this study was to evaluate the efficacy of an intravascular ultrasound (IVUS)-guided strategy for patients with angiographically indeterminate left main coronary artery (LMCA) disease. BACKGROUND: The assessment of LMCA lesions using coronary angiography is often challenging; IVUS provides useful information for assessment of coronary disease. METHODS: Intravascular ultrasound was performed on 121 patients with angiographically normal LMCAs to determine the lower range of normal minimum lumen area (MLA), defined as the mean - 2 SD. We conducted IVUS studies on 214 patients with angiographically indeterminate LMCA lesions, and deferral of revascularization was recommended when the MLA was larger than this predetermined value. RESULTS: The lower range of normal LMCA MLA was 7.5 mm(2). Of the patients with angiographically indeterminate LMCAs, 83 (38.8%) had an MLA <7.5 mm(2), and 131 (61.2%) an MLA > or =7.5 mm(2). Left main coronary artery revascularization was performed in 85.5% (71 of 83) of patients with an MLA <7.5 mm(2) and deferred in 86.9% (114 of 131) of patients with an MLA > or =7.5 mm(2). Long-term follow-up (mean 3.3 +/- 2.0 years) showed no significant difference in major adverse cardiac events (target vessel revascularization, acute myocardial infarction, and death) between patients with an MLA <7.5 mm(2) who underwent revascularization and those with an MLA > or =7.5 mm(2) deferred for revascularization (p = 0.28). Based on outcome, the best cut-off MLA by receiver operating characteristic was 9.6 mm(2). Multivariate predictors of cardiac events were age, smoking, and number of non-LMCA vessels diseased. CONCLUSIONS: Intravascular ultrasound is an accurate method to assess angiographically indeterminate lesions of the LMCA. Furthermore, deferring revascularization for patients with a minimum lumen area > or =7.5 mm(2) appears to be safe.
BACKGROUND: Observed rates of restenosis after drug-eluting stenting are low (<10%). Identification of a reliable and powerful angiographic end point will be useful in future trials. METHODS AND RESULTS: Late loss (postprocedural minimum lumen diameter minus 8-month minimum lumen diameter) was measured in the angiographic cohorts of the SIRIUS (n=703) and E-SIRIUS (n=308) trials. Two techniques, the standard normal approximation and an optimized power transformation, were used to predict binary angiographic restenosis rates and compare them with observed restenosis rates. The mean in-stent late loss observed in the SIRIUS trial was 0.17+/-0.45 mm (sirolimus) versus 1.00+/-0.70 mm (control). If a normal distribution was assumed, late loss accurately estimated in-stent binary angiographic restenosis for the control arm (predicted 35.4% versus observed 35.4%) but underestimated it in the sirolimus arm (predicted 0.6% versus observed 3.2%). Power transformation improved the reliability of the estimate in the sirolimus arm (predicted 3.2% [CI 1.0% to 6.7%]) with similar improvements in the E-SIRIUS trial (predicted 4.0% [CI 1.2% to 7.0%] versus observed 3.9%). In the sirolimus-eluting stent arm, in-stent late loss correlated better with target-lesion revascularization than in-segment late loss (c-statistic=0.915 versus 0.665). CONCLUSIONS: Because distributions of late loss with a low mean are right-skewed, the use of a transformation improves the accuracy of predicting low binary restenosis rates. Late loss is monotonically correlated with the probability of restenosis and yields a more efficient estimate of the restenosis process in the era of lower binary restenosis rates.
Explore the source record for details and available documents.
Our goal was to examine the incidence and consequences of stent loss during percutaneous coronary intervention (PCI) and the retrieval techniques used. We retrospectively reviewed 11,773 consecutive PCI cases involving stents performed at our institution between January 1994 and March 2004 to identify cases of stent loss. Stent loss occurred in 38 of 11,773 PCI procedures involving stents (0.32%; 95% CI = 0.23-0.44%). Mean age of the patients was 67 +/- 11 years and 82% were men. Stent loss occurred more frequently in lesions with calcification and/or significant proximal angulation. In three patients, the stent was crushed and covered with another stent without attempting retrieval. Stent retrieval was attempted in 35 of 38 cases and was successful in 30 (86%). The following retrieval methods were used (more than one method was used in some cases): advancing a balloon through the stent, inflating the balloon, and withdrawing the stent (45%); twirling two wires around the stent (5%); loop snare (26%); biliary forceps (12%); Cook retained fragment retriever (10%); and basket retrieval device (2%). Patients in whom stent loss occurred had a higher incidence of bleeding requiring transfusion (24% vs. 7%; P < 0.001) and more often required emergency coronary artery bypass surgery (5% vs. 0.4%; P < 0.001). No patients in whom the stent was crushed or deployed in the coronary artery had any major cardiac complication. Stent loss during PCI occurs infrequently. Lost stents can be successfully retrieved in the majority of cases using a variety of retrieval techniques, yet stent loss is associated with an increased risk of complications. Stent deployment or crushing may be a good alternative to retrieval.