Search

Background: Contrast-associated acute kidney injury (CA-AKI) after percutaneous coronary intervention is associated with increased mortality. We assessed the effectiveness of an electronic health records safe contrast limit tool in predicting CA-AKI risk and reducing contrast use and CA-AKI., Methods: We created an alert displaying the safe contrast limit to cardiac catheterization laboratory staff prior to percutaneous coronary intervention. The alert used risk factors automatically extracted from the electronic health records. We included procedures from June 1, 2020 to October 1, 2021; the intervention went live February 10, 2021. Using difference-in-differences analysis, we evaluated changes in contrast volume and CA-AKI rates after contrast limit tool implementation compared to control hospitals. Cardiologists were surveyed prior to and 9 months after alert implementation on beliefs, practice patterns, and safe contrast estimates for example patients., Results: At the one intervention site, there were 508 percutaneous coronary interventions before and 531 after tool deployment. At 15 control sites, there were 3550 and 3979 percutaneous coronary interventions, respectively. The contrast limit predicted CA-AKI with an accuracy of 64.1%, negative predictive value of 93.3%, and positive predictive value of 18.7%. After implementation, in high/modifiable risk patients (defined as having a calculated contrast limit <500ml) there was a small but significant -4.60 mL/month (95% CI, -8.24 to -1.00) change in average contrast use but no change in CA-AKI rates (odds ratio, 0.96 [95% CI, 0.84-1.10]). Low-risk patients had no change in contrast use (-0.50 mL/month [95% CI, -7.49 to 6.49]) or CA-AKI (odds ratio, 1.24 [95% CI, 0.79-1.93]). In assessing CA-AKI risk, clinicians heavily weighted age and diabetes but often did not consider anemia, cardiogenic shock, and heart failure., Conclusions: Clinicians often used a simplified assessment of CA-AKI risk that did not include important risk factors, leading to risk estimations inconsistent with established models. Despite clinician skepticism, an electronic health records-based contrast limit tool more accurately predicted CA-AKI risk and was associated with a small decrease in contrast use during percutaneous coronary intervention but no change in CA-AKI rates.

Importance: Guidelines endorse routine coronary angiography and percutaneous coronary intervention (PCI) to screen for and treat cardiac allograft vasculopathy in heart transplant recipients. However, the current Appropriate Use Criteria for Revascularization (AUC-R) do not recognize prior heart transplant as a unique PCI indication. Whether this affects rates of rarely appropriate (RA) PCIs is unknown., Objective: To assess the rate of RA PCI procedures in heart transplant recipients and how it pertains to hospital PCI appropriateness metrics and pay-for-performance scorecards., Design, Setting, and Participants: This observational study used National Cardiovascular Data Registry CathPCI Registry data on all patients undergoing elective PCIs from 96 Medicare-approved heart transplant centers from quarter 3 of 2009 to quarter 2 of 2017. The data were analyzed in July 2018., Exposures: Prior heart transplant., Main Outcomes and Measures: Rates of RA elective PCIs in heart transplant recipients compared with nonrecipients and hospital rates of RA PCI before vs after exclusion of heart transplant recipients using paired t tests. In a subset of heart transplant centers participating in the Anthem Blue Cross and Blue Shield's Quality-In-Sights Hospital Incentive Program (Q-HIP), we compared the change in Q-HIP scorecards before vs after excluding heart transplant recipients., Results: Of 168 802 participants, 123 124 (72.9%) were men, 137 457 were white, and the mean (SD) age was 66.3 (11.4) years. Of 168 802 elective PCIs performed in heart transplant centers, 1854 (1.1%) were for heart transplant recipients. Heart transplant recipients were less likely to have ischemic symptoms (14.6% vs 61.4%, P < .001), had lower rates of antecedent stress testing (15.0% vs 58.4%, P < .001), and had higher RA PCI rates (66.0% vs 16.9%, P < .001) compared with nonrecipients. In heart transplant centers, the absolute difference in RA rates (before vs after excluding transplant recipients) was directly associated with the proportion of PCIs performed in heart transplant recipients (r = 0.91; P < .001). In the subset of heart transplant centers participating in Q-HIP during the 2016 and 2017 calendar years, 8 of 20 (40%) and 8 of 16 centers (50%), respectively, could have benefited from a change in their Q-HIP scorecards if their RA PCI rates excluded transplant recipients., Conclusions and Relevance: Two-thirds of PCIs in heart transplant recipients were deemed RA by the AUC-R. The failure of the AUC-R to consider prior heart transplant as a unique PCI indication may lead to inflated RA PCI rates with the potential for affecting quality reporting and pay-for-performance metrics in heart transplant centers.

Background: Prehospital ECG-based cardiac catheterization laboratory (CCL) activation for ST-segment-elevation myocardial infarction reduces door-to-balloon times, but CCL cancellations (CCL X ) remain a challenging problem. We examined the reasons for CCL X , clinical characteristics, and outcomes of patients presenting as ST-segment-elevation myocardial infarction activations who receive emergent coronary angiography (EA) compared with CCL X ., Methods and Results: We reviewed all consecutive CCL activations between January 1, 2012, and December 31, 2014 (n=1332). Data were analyzed comparing 2 groups stratified as EA (n=466) versus CCL X (n=866; 65%). Reasons for CCL X included bundle branch block (21%), poor-quality prehospital ECG (18%), non-ST-segment-elevation myocardial infarction ST changes (18%), repolarization abnormality (13%), and arrhythmia (8%). A multivariate logistic regression model using age, peak troponin, and initial ECG findings had a high discriminatory value for determining EA versus CCL X (C statistic, 0.985). CCL X subjects were older and more likely to be women, have prior coronary artery bypass grafting, or a paced rhythm ( P<0.0001 for all). All-cause mortality did not differ between groups at 1 year or during the study period (mean follow-up, 2.186±1.167 years; 15.8% EA versus 16.2% CCL X ; P=0.9377). Cardiac death was higher in the EA group (11.8% versus 3.0%; P<0.0001). After adjusting for clinical variables associated with survival, CCL X was associated with an increased risk for all-cause mortality during the study period (hazard ratio, 1.82; 95% CI, 1.28-2.59; P=0.0009)., Conclusions: In this study, prehospital ECG without overreading or transmission lead to frequent CCL X . CCL X subjects differ with regard to age, sex, risk factors, and comorbidities. However, CCL X patients represent a high-risk population, with frequently positive cardiac enzymes and similar short- and long-term mortality compared with EA. Further studies are needed to determine how quality improvement initiatives can lower the rates of CCL X and influence clinical outcomes.

Hypertriglyceridemia-induced pancreatitis is a serious complication of familial dyslipidemias. Hormonal influences during pregnancy can compromise otherwise controlled lipid levels in women with familial hypertriglyceridemia and predispose to pancreatitis leading to increased morbidity in both mother and fetus. We report the successful use of therapeutic plasma exchange (TPE) in the management of hypertriglyceridemia during pregnancy resulting in avoidance of pancreatitis and delivery of a healthy term infant. Thirteen TPEs were performed from 19 to 36 weeks gestation to maintain tight control of triglyceride levels., ((c) 2009 Wiley-Liss, Inc.)

Background: Preservation of luminal area and symmetry in the presence of irregular plaques necessitates local expansion of the artery wall., Methods and Results: Cross-sectional dimensions of coronary arteries in 65 patients were measured with the use of intravascular ultrasound. A total of 104 arterial segments were studied, of which 88 had atherosclerosis; 16 served as nonatherosclerotic control segments. Three features of atherosclerotic arterial segments were classified: (1) plaque formation, (2) lumen shape, and (3) shape of arterial external elastic lamina. With our intravascular ultrasound-based three-level classification system, we identified three patterns that accounted for 89% of all atherosclerotic arterial segments: (1) concentric plaque with a circular lumen and a circular external elastic lamina (n= 17), (2) eccentric plaque with a circular lumen and an oval external elastic lamina (n=35), and (3) eccentric plaque with an oval lumen and a circular external elastic lamina (n=26). A circular lumen was preserved in 66% of all atherosclerotic arterial segments. Arterial segments with a circular lumen in the presence of an eccentric plaque had a significantly larger lumen area than the other two main groups (P<.05)., Conclusions: With our intravascular ultrasound-based classification, we provided information regarding the local remodeling response in the coronary artery wall. In a majority of cases, a circular lumen is maintained. Failure of this highly localized response to be operative may contribute to the development of stenotic lesions at a specific site in the artery.

Background: Uncertainty exists regarding the effects of nitroglycerin on atherosclerotic segments of coronary arteries, and information on vasoreactivity of saphenous vein bypass grafts is sparse. Intravascular ultrasound enables identification of atherosclerosis in angiographically normal segments and allows continuous determination of alterations in cross-sectional lumen areas., Methods and Results: Patients with documented coronary atherosclerosis were studied. Vessel morphology and lumen area at baseline and after 100 to 200 micrograms nitroglycerin were assessed at 10-second intervals for 60 seconds in vessel segments without angiographically apparent lesions. Coronary artery saphenous vein bypass grafts from 11 patients were compared with native coronary arteries in 16 different patients. Atherosclerosis was present in all vessel segments studied. There was a rapid increase in lumen area compared with baseline after intravascular nitroglycerin in both native coronary arteries and saphenous vein bypass grafts. Maximum lumen area dilatation was 19.6 +/- 12.2% in saphenous vein bypass grafts and 19.7 +/- 13.1% in native coronary arteries. An earlier peak response in saphenous vein bypass grafts (34.5 +/- 6.9 seconds) compared with native coronary arteries (44.7 +/- 8.5 seconds; P = .003) was found. Vessel wall area remained constant during vasodilation, but there was a significant reduction in measured wall thickness (P = .034)., Conclusions: In patients with documented coronary artery disease, intravascular ultrasound reveals substantial atherosclerosis in angiographically normal vessel segments. In these vessel segments, both native coronary arteries and saphenous vein bypass grafts exhibit prompt vasodilation with the intravascular administration of nitroglycerin. The vasodilatory capacity in response to nitroglycerin seems to be preserved in transposed, denervated, and devascularized saphenous veins.

Background: No in vivo data are available on the occurrence of compensatory enlargement or vessel constriction in diseased human coronary saphenous vein bypass grafts (SVBGs). The aim of this intravascular ultrasound (IVUS) study was to examine to what extent lumen reduction is accompanied by (1) vessel wall thickening and (2) arterial wall constriction in SVBGs., Methods and Results: We used IVUS to examine 43 SVBGs from 42 patients (32 men, 10 women; mean age, 72 +/- 5 years) 8 to 23 (11 +/- 4) years after SVBG. IVUS images were obtained with a 3.5F monorail ultrasound catheter with a 30-MHz frequency and were analyzed at the lesion site, the reference site, and an intermediate site. The lumen area was significantly (P < .01) decreased; the vessel wall area (SVBG cross-sectional area minus lumen area) and the plaque area (area within the external elastic lamina minus lumen area) were significantly (P < .01) increased from the reference site through the lesion site. However, SVBG cross-sectional area was the same at these three sites (24.0 +/- 8.1 versus 24.4 +/- 8.6 versus 24.5 +/- 8.6 mm2, P = NS), and the external elastic lamina area was also quite constant in each vessel (17.8 +/- 6.0 versus 17.7 +/- 6.4 versus 17.6 +/- 6.2 mm2, P = NS)., Conclusions: These in vivo IVUS data from human coronary SVBGs demonstrate that (1) no focal compensatory enlargement or vessel constriction occurred in stenotic segments compared with the reference segments and that (2) the absence of focal compensatory enlargement appears to be a potentially important factor in the progression of stenoses in coronary SVBGs.

The aim of this study was to determine the effect of intravascular ultrasound (IVUS) imaging on decision making in the performance of coronary interventions. One hundred lesions were assessed in 87 patients undergoing balloon or laser angioplasty, atherectomy, stent placement, and additional diagnostic examination. Angiographically acceptable results were deemed inadequate by IVUS in 29% of angioplasties and 30% of stent deployments, and planned procedures subsequently were altered. Abnormalities commonly identified by IVUS and not by angiography were 13 coronary dissections after the procedure and 14 significant stenoses in apparently normal angiograms and significant stenoses were excluded in 7 patients with ambiguous angiograms. The apparent contribution of coronary IVUS imaging led to its significantly increased use over a 1-year period, as coronary interventional decisions on the basis of IVUS findings increased from 4 (17%) of 19 to 60 (74%) of 81. These data suggest that IVUS is a useful adjunct to angiography in selected patients for (1) identification or exclusion of dissection, (2) assessment of the adequacy of balloon angioplasty, (3) identification or exclusion of thrombus, (4) measurement of the depth of tissue removal, (5) determination of stent size and the result of stent deployment, and (6) assessment of the severity of stenoses, especially at ostial sites.

Objectives: This study assessed the efficacy of a new high intensity, low frequency therapeutic coronary ultrasound catheter for thrombus dissolution in vitro and in vivo in canine coronary arteries., Background: Therapeutic ultrasound has been shown to dissolve thrombi in vitro and in peripheral arteries in vivo. There have been no previous studies on in vivo coronary thrombus dissolution by ultrasound., Methods: In vitro, we exposed 1- to 4-h old human blood clots for 3 min to pulsed-wave ultrasound. Clot dissolution under various conditions was evaluated. In vivo occlusive coronary thrombi were induced in 18 dogs., Results: In vitro irrigation alone (10 ml/min of normal saline solution) and ultrasound alone each contributed to a reduction of clot weight by 47.1 +/- 11.4 mg and 84.6 +/- 25.6 mg, respectively, after 3 min (p < 0.001). Ultrasound plus irrigation resulted in a reduction of clot weight by 216.5 +/- 31.5 mg after 3 min (p < 0.001). The magnitude of clot dissolution was considerably amplified when ultrasound energy was combined with irrigation, probably because of cavitational effects. In vivo, in three dogs mechanical passage of the unactivated probe failed to recanalize the artery, and the arteries remained thrombotically occluded. After passage of the activated ultrasound probe, angiography revealed widely patent coronary arteries in 13 of 15 dogs and partial recanalization with filling defects indicative of residual thrombus in 2 of 15 dogs. Three of 15 coronary arteries were histologically free of residual thrombi. Mural thrombi extending to < or = 10% of the vessel circumference were seen in 10 of 15 dogs. Residual thrombi > or = 50% of the vessel circumference were found in two cases. There was no histologic evidence of ultrasound-mediated vessel damage., Conclusions: Catheter-delivered therapeutic ultrasound effectively dissolves clots in vitro and in canine coronary arteries in vivo. Thus, therapeutic catheter-delivered ultrasound has the potential to serve as an adjunct or alternative treatment for thrombus-mediated coronary ischemic syndromes or myocardial infarction.

Intra-aortic balloon pumping (IABP) was attempted in 112 consecutive patients, resulting in successful placement in 49 of 50 (98%) patients when the percutaneous technique was used and in 60 of 62 (97.3%) patients when the surgical technique was used. Complications following acute myocardial infarction and perioperative problems were the two most frequent (47% and 52%, respectively) indications for IABP. A favorable survival was observed in patients with acute myocardial infarction with ventricular septal defect undergoing surgery after IABP (80%) and in patients in whom IABP was used in the perioperative setting (57.6%); survival remained poor in patients with postinfarction shock or severe heart failure (20% and 23%, respectively). Complications related to IABP occurred in 23 (20.5% patients but tended to occur more frequently in patients undergoing placement by the percutaneous route than by the surgical route (31% vs 9.6%; p less than 0.03) and in patients over age 70. Thus IABP can be successfully inserted in the majority of patients, but the high complication rate, especially with the percutaneous route, suggests caution in its indiscriminate use, particularly in patients whose mortality remains high despite its use.