Impact of the COVID-19 pandemic on interventional cardiology fellowship training in the New York metropolitan area: A perspective from the United States epicenter.

BACKGROUND: The healthcare burden posed by the coronavirus disease 2019 (COVID-19) pandemic in the New York Metropolitan area has necessitated the postponement of elective procedures resulting in a marked reduction in cardiac catheterization laboratory (CCL) volumes with a potential to impact interventional cardiology (IC) fellowship training. METHODS: We conducted a web-based survey sent electronically to 21 Accreditation Council for Graduate Medical Education accredited IC fellowship program directors (PDs) and their respective fellows. RESULTS: Fourteen programs (67%) responded to the survey and all acknowledged a significant decrease in CCL procedural volumes. More than half of the PDs reported part of their CCL being converted to inpatient units and IC fellows being redeployed to COVID-19 related duties. More than two-thirds of PDs believed that the COVID-19 pandemic would have a moderate (57%) or severe (14%) adverse impact on IC fellowship training, and 21% of the PDs expected their current fellows' average percutaneous coronary intervention (PCI) volume to be below 250. Of 25 IC fellow respondents, 95% expressed concern that the pandemic would have a moderate (72%) or severe (24%) adverse impact on their fellowship training, and nearly one-fourth of fellows reported performing fewer than 250 PCIs as of March 1st. Finally, roughly one-third of PDs and IC fellows felt that there should be consideration of an extension of fellowship training or a period of early career mentorship after fellowship. CONCLUSIONS: The COVID-19 pandemic has caused a significant reduction in CCL procedural volumes that is impacting IC fellowship training in the NY metropolitan area. These results should inform professional societies and accreditation bodies to offer tailored opportunities for remediation of affected trainees.

Gender Differences in the Outcomes of Drug-Coated Balloon Treatment in Symptomatic Femoropopliteal Arterial Disease.

OBJECTIVES: To assess 24-month outcome differences based on sex in symptomatic femoro-popliteal arterial disease of patients treated with drug-coated balloon (DCB). BACKGROUND: Peripheral artery disease affects over 12 million people in the United States. Drug-coated balloons have shown to be effective in treating patients with symptomatic femoropopliteal arterial occlusive disease. Debate remains regarding its safety and efficacy in female gender. We investigated the differential treatment effect between genders. METHODS: Patients (93 females and 102 males) with symptomatic femoropopliteal arterial disease treated with DCB from November 2014 to November 2015 were included in this retrospective study. We compared the resting ankle-brachial indices (ABIs) and peak systolic velocities (PSVs) by arterial duplex between the male and female patients at 6, 12, and 24 months postintervention. RESULTS: Females had significantly smaller vessels (4.70 ± 0.9, P = .02) and higher body mass index (BMI; 30.0 ± 3.7, P = .002) than males. Females had significantly decreased ABI and PSV at the 6-month (ABI: 0.90 ± 0.15, P = .05 and PSV: 188.30 ± 103.1, P = .02), 12-month (ABI: 0.86 ± 0.15, P < .0001 and PSV: 219.10 ± 100.10, P = .001), and at 24-month (ABI: 0.84 ± 0.2, P = .0001 and PSV: 251.0 ± 135.9, P < .0001) intervals when compared to males. Females had increased clinically driven target lesion revascularization (TLR) at 6 months (females = 8 vs males = 4, P = .22), 12 months (females = 12 vs males = 4, P = .02), and 24 months (females = 14 vs males = 6, P = .03). In simple logistic regression analysis, BMI, age, reference vessel diameter (RVD), and gender were strongly associated with target lesion restenosis. The final model included the above and it produced the following odds ratios (ORs): BMI (OR = 1.07, 95% confidence interval [CI]: 0.98-1.2), age (OR: 1.0, CI: 0.96-1.03), RVD (OR: 1.6, CI: 1.02-2.4), and gender (OR: 3.5, CI: 1.6-7.8). CONCLUSION: Females treated with DCBs have significantly decreased ABI, PSVs, and an increased rate of TLR than their male counterparts.

Trends and Outcomes of Intravascular Imaging-guided Percutaneous Coronary Intervention in the United States.

INTRODUCTION: Intravascular imaging-guided percutaneous coronary intervention (PCI) has shown to improve outcomes in randomized controlled trials. However, there are little real-world data about intravascular imaging utilization during PCI and its outcomes in the United States. METHODS: We conducted an observational analysis on the use of intravascular imaging (Intravascular Ultrasound or Optical Coherence Tomography)-guided PCI in 2,425,036 patients undergoing PCI between January 2010 and December 2014 from the Nationwide Inpatient Sample database. Utilizing propensity score matching, 83,988 matched pairs were identified. The primary outcome was in-hospital mortality. The secondary outcomes included cardiogenic shock and acute kidney injury. RESULTS: Among the 2,425,036 patients, 161,808 (6.7%) underwent imaging-guided PCI. Use of imaging-guidance increased from 6% in 2010 to 6.6% in 2014 (Ptrend < 0.001). The in-hospital mortality was significantly different between imaging-guided PCI and angiography-guided PCI [1.0% vs. 1.5%; adjusted OR: 0.67; 95% confidence interval (CI): 0.54-0.83, P < 0.001]. The rates of cardiogenic shock (2.5% vs. 3.1%; adjusted OR: 0.78; 95% CI: 0.66-0.93; P = 0.005) were significantly lower in imaging-guided PCI group and acute kidney injury rates (7.0% vs. 7.1%; adjusted OR: 0.99; 95% CI: 0.89-1.12; P = 0.919) were not significantly different. CONCLUSIONS: Imaging-guided PCI is associated with lower in-hospital mortality. Yet, a small proportion of patients undergoing PCI have imaging-guidance.

Frequency of 30-day readmission and its causes after percutaneous coronary intervention in acute myocardial infarction complicated by cardiogenic shock.

BACKGROUND: Survival after percutaneous coronary intervention (PCI) in acute myocardial infarction complicated by cardiogenic shock (AMI-CS) has increased over the years. Short-term readmission rates in this high-risk population remain unknown. METHODS: We queried the United States (U.S.) Nationwide Readmission Database (NRD) from January 2010 to November 2014 using the International Classification of Diseases-Ninth edition, Clinical Modification (ICD-9 CM) codes to identify all patients ≥18 years readmitted within 30 days after surviving an index hospitalization for PCI in AMI-CS. Incidence, etiologies, and predictors of 30-day readmission were analyzed. RESULTS: Among 46,435 patients who survived to discharge after PCI in AMI-CS, 9,020 (19.4%) were readmitted within 30 days. Median time to 30-day readmission was 11 days. Cardiac conditions were the most common causes of readmission (57.8%). Heart failure was the leading readmission diagnosis (24.8%). Private insurance including HMO and self-pay were predictive of lower 30-day readmission. Among other covariates, female sex, comorbidities such as heart failure, atrial fibrillation, in-hospital complications such as major bleeding, sepsis, respiratory complications, AKI requiring dialysis, utilization of mechanical circulatory support (IABP and ECMO) were independently predictive of 30-day readmission. Trend analysis showed decline in 30-day readmission rates from 21.9% in 2010 to 17.9% in 2014 (ptrend < 0.001). CONCLUSION: In this large real-world database, one in five patients receiving PCI in AMI-CS was readmitted within 30 days after discharge. Cardiac conditions were the most common causes of readmission. Insurance type had significant influence on 30-day readmission.

Tailoring Antiplatelet Therapy Intensity to Ischemic and Bleeding Risk.

BACKGROUND: Balancing ischemic and bleeding risk is an evolving framework. METHODS AND RESULTS: Our objectives were to simulate changes in risks for adverse events and event-driven costs with use of ticagrelor or prasugrel versus clopidogrel according to varying levels of ischemic and bleeding risk. Using the validated PARIS risk functions, we estimated 1-year ischemic (myocardial infarction or stent thrombosis) and bleeding (Bleeding Academic Research Consortium types 3 or 5) event rates among PARIS study participants who underwent percutaneous coronary intervention with drug-eluting stent implantation for an acute coronary syndrome and were discharged with aspirin and clopidogrel (n=1497). Simulated changes in adverse events with ticagrelor or prasugrel were calculated by applying treatment effects from randomized trials for a 1-year time horizon. Event costs were estimated using National Inpatient Sample data. Net costs were calculated between antiplatelet therapy groups according to level of ischemic and bleeding risk. After weighting events for quality-of-life impact, we calculated event rates and costs for risk-tailored treatment versus clopidogrel under multiple drug pricing assumptions. One-year rates (per 1000 person-years) for ischemic events were 12.6, 24.1, and 66.1, respectively, among those at low (n=630), intermediate (n=536), and high (n=331) ischemic risk. Analogous bleeding rates were 11.0, 23.9, and 66.2, respectively, among low (n=728), intermediate (n=634), and high (n=135) bleeding risk patients. Mean per event costs were $22 174 (ischemic) and $12 203 (bleeding). When risks for ischemia matched or exceeded bleeding, simulated utility-weighted event rates favored ticagrelor/prasugrel, whereas clopidogrel reduced utility-weighted events when bleeding exceeded ischemic risk. One-year costs were sensitive to drug pricing assumptions, and risk-tailored treatment with either agent progressed from cost incurring to cost saving with increasing generic market share. CONCLUSIONS: Tailoring antiplatelet therapy intensity to patient risk may improve health utility and could produce cost savings in the first year after percutaneous coronary intervention. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00998127.

Use of prasugrel and clinical outcomes in African-American patients treated with percutaneous coronary intervention for acute coronary syndromes.

OBJECTIVE: To investigate the use of prasugrel after percutaneous coronary intervention (PCI) in African American (AA) patients presenting with acute coronary syndrome (ACS). BACKGROUND: AA patients are at higher risk for adverse cardiovascular outcomes after PCI and may derive greater benefit from the use of potent antiplatelet therapy. METHODS: Using the multicenter PROMETHEUS observational registry of ACS patients treated with PCI, we grouped patients by self-reported AA or other races. Clinical outcomes at 90-day and 1-year included non-fatal myocardial infarction (MI), major adverse cardiac events (composite of death, MI, stroke, or unplanned revascularization) and major bleeding. RESULTS: The study population included 2,125 (11%) AA and 17,707 (89%) non-AA patients. AA patients were younger, more often female (46% vs. 30%) with a higher prevalence of diabetes mellitus, chronic kidney disease, and prior coronary intervention than non-AA patients. Although AA patients more often presented with troponin (+) ACS, prasugrel use was much less common in AA vs. non-AA (11.9% vs. 21.4%, respectively, P = 0.001). In addition, the use of prasugrel increased with the severity of presentation in non-AA but not in AA patients. Multivariable logistic regression showed AA race was an independent predictor of reduced use of prasugrel (0.42 [0.37-0.49], P < 0.0001). AA race was independently associated with a significantly higher risk of MI at 90-days and 1 year after PCI. CONCLUSIONS: Despite higher risk clinical presentation and worse 1-year ischemic outcomes, AA race was an independent predictor of lower prasugrel prescription in a contemporary population of ACS patients undergoing PCI.

Assessment of trans-aortic pressure gradient using a coronary pressure wire in patients with mechanical aortic and mitral valve prostheses.

Accurate evaluation of trans-aortic valvular pressure gradients is challenging in cases where dual mechanical aortic and mitral valve prostheses are present. Non-invasive Doppler echocardiographic imaging has its limitations due to multiple geometric assumptions. Invasive measurement of trans-valvular gradients with cardiac catheterization can provide further information in patients with two mechanical valves, where simultaneous pressure measurements in the left ventricle and ascending aorta must be obtained. Obtaining access to the left ventricle via the mitral valve after a trans-septal puncture is not feasible in the case of a concomitant mechanical mitral valve, whereas left ventricular apical puncture technique is associated with high procedural risks. Retrograde crossing of a bileaflet mechanical aortic prosthesis with standard catheters is associated with the risk of catheter entrapment and acute valvular regurgitation. In these cases, the assessment of trans-valvular gradients using a 0.014˝ diameter coronary pressure wire technique has been described in a few case reports. We present the case of a 76-year-old female with rheumatic valvular heart disease who underwent mechanical aortic and mitral valve replacement in the past. She presented with decompensated heart failure and echocardiographic findings suggestive of elevated pressure gradient across the mechanical aortic valve prosthesis. The use of a high-fidelity 0.014˝ diameter coronary pressure guidewire resulted in the detection of a normal trans-valvular pressure gradient across the mechanical aortic valve. This avoided a high-risk third redo valve surgery in our patient. © 2017 Wiley Periodicals, Inc.

Three-dimensional volumetric assessment of coronary artery calcification in patients with stable coronary artery disease by OCT.

AIMS: There is a lack of a reliable technique to quantify coronary artery calcification (CAC). Hence, we used optical coherence tomography (OCT) to quantitate three-dimensional CAC volume to examine its association with plaque characteristics. METHODS AND RESULTS: A total of 250 patients with stable angina undergoing OCT imaging before PCI were included. CAC volume was calculated from every frame of the culprit lesion and divided into tertiles (low, intermediate and high). Quantitative calcium characteristics were assessed in 107 patients who underwent both OCT and IVUS. Increase in CAC volume was associated with reduced lipid volume index, lipid length and number of lipid plaques. Diabetes and LDL cholesterol predicted less coronary calcification whereas age and prior MI predicted increased CAC after adjusting for all clinical factors. Lipid volume index (ρ=-0.001 [-0.003 to -0.00003]; p=0.04) and mean calcium depth (ρ=-0.02 [-0.02 to -0.01]; p=0.000) were inversely related to CAC volume after adjusting for all OCT characteristics, whereas cap thickness increased with increase in CAC volume (ρ=0.01 [0.002-0.03]; p=0.02) only in unadjusted analysis. Regression analysis demonstrated a significant correlation between calcium length (ρ=0.83; p<0.001) and calcium arc (ρ=0.86; p<0.001) measured by IVUS and OCT. CONCLUSIONS: Target lesions with high CAC volume are characterised by reduced plaque lipid content and calcium closer to the luminal border. Fibrous cap thickness increased with increase in calcium volume.

Impact of an integrated treatment algorithm based on platelet function testing and clinical risk assessment: results of the TRIAGE Patients Undergoing Percutaneous Coronary Interventions To Improve Clinical Outcomes Through Optimal Platelet Inhibition study.

Assessment of platelet reactivity alone for thienopyridine selection with percutaneous coronary intervention (PCI) has not been associated with improved outcomes. In TRIAGE, a prospective multicenter observational pilot study we sought to evaluate the benefit of an integrated algorithm combining clinical risk and platelet function testing to select type of thienopyridine in patients undergoing PCI. Patients on chronic clopidogrel therapy underwent platelet function testing prior to PCI using the VerifyNow assay to determine high on treatment platelet reactivity (HTPR, ≥230 P2Y12 reactivity units or PRU). Based on both PRU and clinical (ischemic and bleeding) risks, patients were switched to prasugrel or continued on clopidogrel per the study algorithm. The primary endpoints were (i) 1-year major adverse cardiovascular events (MACE) composite of death, non-fatal myocardial infarction, or definite or probable stent thrombosis; and (ii) major bleeding, Bleeding Academic Research Consortium type 2, 3 or 5. Out of 318 clopidogrel treated patients with a mean age of 65.9 ± 9.8 years, HTPR was noted in 33.3 %. Ninety (28.0 %) patients overall were switched to prasugrel and 228 (72.0 %) continued clopidogrel. The prasugrel group had fewer smokers and more patients with heart failure. At 1-year MACE occurred in 4.4 % of majority HTPR patients on prasugrel versus 3.5 % of primarily non-HTPR patients on clopidogrel (p = 0.7). Major bleeding (5.6 vs 7.9 %, p = 0.47) was numerically higher with clopidogrel compared with prasugrel. Use of the study clinical risk algorithm for choice and intensity of thienopyridine prescription following PCI resulted in similar ischemic outcomes in HTPR patients receiving prasugrel and primarily non-HTPR patients on clopidogrel without an untoward increase in bleeding with prasugrel. However, the study was prematurely terminated and these findings are therefore hypothesis generating.

Plaque Characterization to Inform the Prediction and Prevention of Periprocedural Myocardial Infarction During Percutaneous Coronary Intervention: The CANARY Trial (Coronary Assessment by Near-infrared of Atherosclerotic Rupture-prone Yellow).

OBJECTIVES: This study sought to determine whether pre-percutaneous coronary intervention (PCI) plaque characterization using near-infrared spectroscopy identifies lipid-rich plaques at risk of periprocedural myonecrosis and whether these events may be prevented by the use of a distal protection filter during PCI. BACKGROUND: Lipid-rich plaques may be prone to distal embolization and periprocedural myocardial infarction (MI) in patients undergoing PCI. METHODS: Patients undergoing stent implantation of a single native coronary lesion were enrolled in a multicenter, prospective trial. Near-infrared spectroscopy and intravascular ultrasound were performed at baseline, and lesions with a maximal lipid core burden index over any 4-mm length (maxLCBI4mm) ≥600 were randomized to PCI with versus without a distal protection filter. The primary endpoint was periprocedural MI, defined as troponin or a creatine kinase-myocardial band increase to 3 or more times the upper limit of normal. RESULTS: Eighty-five patients were enrolled at 9 U.S. sites. The median (interquartile range) maxLCBI4mm was 448.4 (274.8 to 654.4) pre-PCI and decreased to 156.0 (75.6 to 312.6) post-PCI (p < 0.0001). Periprocedural MI developed in 21 patients (24.7%). The maxLCBI4mm was higher in patients with versus without MI (481.5 [425.6 to 679.6] vs. 371.5 [228.9 to 611.6], p = 0.05). Among 31 randomized lesions with maxLCBI4mm ≥600, there was no difference in the rates of periprocedural MI with versus without the use of a distal protection filter (35.7% vs. 23.5%, respectively; relative risk: 1.52; 95% confidence interval: 0.50 to 4.60, p = 0.69). CONCLUSIONS: Plaque characterization by near-infrared spectroscopy identifies lipid-rich lesions with an increased likelihood of periprocedural MI after stent implantation, presumably due to distal embolization. However, in this pilot randomized trial, the use of a distal protection filter did not prevent myonecrosis after PCI of lipid-rich plaques.

Optical coherence tomography assessment of the mechanistic effects of rotational and orbital atherectomy in severely calcified coronary lesions.

OBJECTIVES: This study sought to assess the mechanistic effect of rotational atherectomy (RA) and orbital atherectomy (OA) on heavily calcified coronary lesions and subsequent stent placement using optical coherence tomography (OCT). BACKGROUND: RA and OA are two main approaches to ablate coronary calcium. While small case reports have described the mechanistic effect of RA in calcified coronary lesions, there has been no imaging study to assess the effect of OA on coronary artery architecture and/or compare the effects of two atherectomy devices. METHODS: This study analyzed 20 consecutive patients with OCT imaging performed after atherectomy and after stent implantation, RA (n = 10) and OA (n = 10). RESULTS: Postatherectomy OCT analysis identified tissue modification with deep dissections in around a third of lesions after RA and OA; however, post OA dissections ("lacunae") were significantly deeper (1.14 vs. 0.82 mm, P = 0.048). Post OA/RA lesions with dissections had significantly higher percentage of lipid rich plaques and smaller calcification arcs as compared to plaques without dissections. Stents after OA were associated with a significantly lower percent of stent strut malapposition than post RA stents (4.36 vs. 8.02%, P = 0.038). CONCLUSIONS: Although the incidence of dissections was comparable between RA and OA cases, OA resulted in deeper tissue modifications (lacunae) as shown by OCT imaging. The finding might provide an explanation for a better stent apposition after OA as compared to RA. Their impact on long-term outcome needs to be determined.

Female gender and mortality after percutaneous coronary intervention: results from a large registry.

OBJECTIVES: To investigate if previously reported gender-based outcome disparities following percutaneous coronary intervention (PCI) are applicable in a large and racially-diverse cohort in the drug eluting stent (DES) era. BACKGROUND: It is generally believed that women suffer inferior outcomes compared to men after PCI. However, various strategies have evolved that may have mitigated this imbalance, including improved medical therapy, attention to risk-factors, and procedural advances of PCI including DES. METHODS: We identified 13,752 patients (4,761 female, 34.6%) with complete follow-up data who underwent de novo lesion PCI from 04/2003 to 04/2009. Relevant data were extracted from an IRB-approved registry. RESULTS: Compared to males, females were significantly older (69.0 vs. 64.8 years) and more frequently from a minority or non-Caucasian background. Females smoked less, but more were hypertensive and/or diabetic. Women had higher HDL, but also higher LDL cholesterol levels. More women presented with an unstable coronary syndrome and required left anterior descending artery PCI. While unadjusted post-PCI mortality rates were higher in females versus males (30 days, 1.3 vs. 0.8%, P = 0.009; 1 year, 6.1 vs. 4.8%, P = 0.001; 3 year, 10.4 vs. 8.4%, P < 0.0001), multivariable regression analyses failed to identify female gender as an independent predictor of mortality. Propensity-adjusted modeling confirmed that females were not at intrinsically higher risk for mortality after PCI. CONCLUSIONS: Females undergoing PCI exhibit more comorbidities and adverse prognostic factors than males. However, risk-adjusted analyses identified that gender is not an independent predictor of mortality after PCI in the DES era.

A novel clinical prediction rule for 30-day mortality following balloon aortic valuloplasty: the CRRAC the AV score.

OBJECTIVES: We seek to identify predictors of 30-day mortality after balloon aortic valvuloplasty (BAV). BACKGROUND: To date, there is no validated method of predicting patient outcomes after percutaneous aortic valve interventions. METHODS: Data for consecutive patients with severe aortic stenosis who underwent BAV at the Mount Sinai Medical Center from January 2001 to July 2007 were retrospectively reviewed. Cox-proportional hazards regression was used to identify significant predictors of 30-day mortality, and the resultant model was compared to the EuroSCORE using Akaike's Information Criterion and area under the receiver-operating curve (AUC). RESULTS: The analysis included 281 patients (age 83 ± 9 years, 61% women, aortic valve area: 0.64 ± 0.2 cm(2)) and 36 (12.8%) of whom died within 30 days of BAV. With identified risk factors for 30-day mortality, critical status, renal dysfunction, right atrial pressure, and cardiac output, we constructed the CRRAC the AV risk score. Thirty-day survival was 72% in the highest tertile versus 94% in the lower two tertiles of the score. Compared to the additive and logistic EuroSCORE, the risk score demonstrated superior discrimination (AUC = 0.75 vs. 0.60 and 0.63, respectively). CONCLUSIONS: We derived a risk score, the CRRAC the AV score that identifies patients at high-risk of 30-day mortality after BAV. Validation of the developed risk prediction score, the CRRAC the AV score, is needed in other cohorts of post-BAV patients and potentially in patients undergoing other catheter-based valve interventions.

Bolus-only versus bolus + infusion of glycoprotein IIb/IIIa inhibitors during percutaneous coronary intervention.

BACKGROUND: The present study was done to analyze if glycoprotein IIb/IIIa inhibitors (GPI) bolus-only will reduce vascular/bleeding complications and cost with similar major adverse cardiac events (MACE) when compared with GPI bolus + infusion. Evidence-based therapy of GPI inhibitors during percutaneous coronary intervention (PCI) incorporates intravenous bolus followed by 12 to 18 hours of infusion. However, GPI bolus + infusion may increase vascular/bleeding complications and may not reduce MACE when compared with GPI bolus-only. METHODS: From January 1, 2003, to December 31, 2004, 2,629 consecutive patients received GPI during PCI at a single center. Of these, 1,064 patients received GPI bolus + infusion in 2003 and were compared with 1,565 patients that received GPI bolus-only in 2004. Baseline characteristics were similar in both groups. RESULTS: Patients receiving GPI bolus-only had reduced vascular/bleeding complications when compared with bolus + infusion (4.9% vs 7%, P < .05, odds ratio 0.62, 95% confidence interval 0.45-0.89). Furthermore, ischemic complications were similar in both groups, including periprocedural creatine kinase-MB enzyme release (12.8% vs 15.3%, P = NS), MACE at 30 days (3.2% vs 3%, P = NS), and death and myocardial infarction at 1 year (7.1% vs 7.8%, P = NS). In addition, GPI bolus-only reduced cost in US dollars ($323 vs $706, P < .001) and increased ambulatory PCI (13.1% vs 3.2%, P < .01), with reduced length of stay (1.1 vs 1.6 days, P < .01), when compared with GPI bolus + infusion. CONCLUSIONS: Glycoprotein inhibitor bolus-only reduces vascular/bleeding complications with similar MACE and reduced cost when compared with GPI bolus + infusion. In addition, GPI bolus-only improved ambulatory PCI and reduced length of stay. These results are consistent with a safer and cost-effective strategy for bolus-only when GPI therapy is considered during PCI.

Coronary angiography, lesion classification and severity assessment.

A joint task force of the American College of Cardiology and the American Heart Association established criteria in 1988 to estimate procedural success and complication rates after balloon angioplasty, based on the presence or absence of specific lesion characteristics. Advances in the technique of coronary intervention over the years have changed the management of patients who have coronary artery disease, resulting in safer and more effective percutaneous revascularization in patients previously deemed at high risk for nonsurgical approaches. Coronary angiography (visual or quantitative) is a simple,easy, and mostly reliable tool in the assessment of lesion severity, but it may be inconclusive in the borderline lesions (40% to 60% diameter obstruction). Anatomical (using intravascular ultrasound) and physiological (using coronary flow reserve or fractional flow reserve) lesion assessment may be required for adequate lesion evaluation, before and after percutaneous coronary intervention.