Thyroid Dysfunction Risk After Iodinated Contrast Media Administration: A Prospective Longitudinal Cohort Analysis.

CONTEXT: Iodinated contrast media (ICM) is a common source of excess iodine in medical settings, given the common use of iodinated radiologic procedures. OBJECTIVE: To determine the long-term risks of thyroid dysfunction following iodinated contrast administration in a prospective study. DESIGN, SETTING, PARTICIPANTS: A longitudinal cohort study was conducted of patients in the U.S. Veterans Affairs medical system who received ICM. MAIN OUTCOME MEASURES: Serum thyroid function, thyroid antibody, and inflammatory markers were measured at baseline. Thyroid function tests were repeated at 1 month, 3 months, and every 6 months thereafter until 36 months. Risk of thyroid dysfunction and longitudinal changes in thyroid hormone levels were assessed using mixed effect models. RESULTS: There were 122 participants (median age, 70.0 [IQR 62.2-74.0] years; 98.4% male). At baseline, six subjects had subclinical thyroid dysfunction prior to ICM receipt. During median follow-up of 18 months, iodine-induced thyroid dysfunction was observed in 11.5% (14/122); six (4.9%) developed hyperthyroidism (including one with overt hyperthyroidism) and eight (6.6%) subclinical hypothyroidism. At last follow-up, ten of 20 subjects with thyroid dysfunction (14 new-onset cases and six with preexisting thyroid dysfunction) had persistent subclinical hyperthyroidism or hypothyroidism. There were also subtle changes in thyroid hormones observed longitudinally within the reference ranges in the overall cohort. CONCLUSIONS: There is a rare long-term risk of an excess iodine load on thyroid dysfunction even among individuals from an overall iodine-sufficient region, supporting the need for targeted monitoring following iodinated contrast administration.

Iodine-Induced Hypothyroidism and Long-Term Risks of Incident Heart Failure.

Background Although most individuals can adapt to a large iodine load and remain euthyroid, hypothyroidism can develop after iodine exposure. Hypothyroidism is associated with adverse cardiovascular consequences, including heart failure. This study was performed to investigate the relationships between iodine-induced hypothyroidism and incident heart failure. Methods and Results This cohort study of the US Veterans Health Administration (1998-2021) included adults aged ≥18 years with a serum thyroid-stimulating hormone (thyrotropin) <60 days of iodine contrast administration, and <1 year of a baseline normal serum thyroid-stimulating hormone. Cox proportional hazards regression ascertained risk of incident heart failure following iodine-induced hypothyroidism, adjusting for age, sex, race and ethnicity, body mass index, and history of coronary heart disease, dyslipidemia, diabetes, and hypertension. Of 45 470 veterans (mean±SD age, 61.1±14.1 years; 88% men), 3361 (7.4%) developed iodine-induced hypothyroidism. Heart failure developed in 5685 (12.5%) individuals over a median follow-up of 3.6 years (interquartile range, 1.9-7.2 years). Adjusted for risk factors, iodine-induced hypothyroidism was associated with increased risk of heart failure, compared with those who remained euthyroid after iodine exposure (adjusted hazard ratio [HR], 1.11 [95% CI, 1.01-1.22]). Women were at greater risk than men (adjusted HR: women, 1.65 [95% CI, 1.13-2.40]; men, 1.08 [95% CI, 0.98-1.19]; P for interaction, 0.02). Conclusions In the largest US study of this topic, hypothyroidism following iodine exposure was associated with an increased risk of incident heart failure, particularly in women. These findings support the need for further research to address the clinical significance of this issue, including the possible sex-specific risks of incident heart failure in more diverse data sets and study populations.

Iodine-Induced Hyperthyroidism and Long-term Risks of Incident Atrial Fibrillation and Flutter.

CONTEXT: Although iodine-induced hyperthyroidism is a potential consequence of iodinated radiologic contrast administration, its association with long-term cardiovascular outcomes has not been previously studied. OBJECTIVE: To investigate the relationships between hyperthyroidism observed after iodine contrast administration and incident atrial fibrillation/flutter. METHODS: Retrospective cohort study of the U.S. Veterans Health Administration (1998-2021) of patients age ≥18 years with a normal baseline serum thyrotropin (TSH) concentration, subsequent TSH <1 year, and receipt of iodine contrast <60 days before the subsequent TSH. Cox proportional hazards regression was employed to ascertain the adjusted hazard ratio (HR) with 95% CI of incident atrial fibrillation/flutter following iodine-induced hyperthyroidism, compared with iodine-induced euthyroidism. RESULTS: Iodine-induced hyperthyroidism was observed in 2500 (5.6%) of 44 607 Veterans (mean ± SD age, 60.9 ± 14.1 years; 88% men) and atrial fibrillation/flutter in 10.4% over a median follow-up of 3.7 years (interquartile range 1.9-7.4). Adjusted for sociodemographic and cardiovascular risk factors, iodine-induced hyperthyroidism was associated with an increased risk of atrial fibrillation/flutter compared with those who remained euthyroid after iodine exposure (adjusted HR 1.19, 95% CI 1.06-1.33). Females were at greater risk for incident atrial fibrillation/flutter than males (females, HR 1.81, 95% CI 1.12-2.92; males, HR 1.15, 95% CI 1.03-1.30; P for interaction = .04). CONCLUSION: Hyperthyroidism following a high iodine load was associated with an increased risk of incident atrial fibrillation/flutter, particularly among females. The observed sex-based differences should be confirmed in a more sex-diverse study sample, and the cost-benefit analysis of long-term monitoring for cardiac arrhythmias following iodine-induced hyperthyroidism should be evaluated.

Team-Based Coaching Intervention to Improve Contrast-Associated Acute Kidney Injury: A Cluster-Randomized Trial.

BACKGROUND: Up to 14% of patients in the United States undergoing cardiac catheterization each year experience AKI. Consistent use of risk minimization preventive strategies may improve outcomes. We hypothesized that team-based coaching in a Virtual Learning Collaborative (Collaborative) would reduce postprocedural AKI compared with Technical Assistance (Assistance), both with and without Automated Surveillance Reporting (Surveillance). METHODS: The IMPROVE AKI trial was a 2×2 factorial cluster-randomized trial across 20 Veterans Affairs medical centers (VAMCs). Participating VAMCs received Assistance, Assistance with Surveillance, Collaborative, or Collaborative with Surveillance for 18 months to implement AKI prevention strategies. The Assistance and Collaborative approaches promoted hydration and limited NPO and contrast dye dosing. We fit logistic regression models for AKI with site-level random effects accounting for the clustering of patients within medical centers with a prespecified interest in exploring differences across the four intervention arms. RESULTS: Among VAMCs' 4517 patients, 510 experienced AKI (235 AKI events among 1314 patients with preexisting CKD). AKI events in each intervention cluster were 110 (13%) in Assistance, 122 (11%) in Assistance with Surveillance, 190 (13%) in Collaborative, and 88 (8%) in Collaborative with Surveillance. Compared with sites receiving Assistance alone, case-mix-adjusted differences in AKI event proportions were -3% (95% confidence interval [CI], -4 to -3) for Assistance with Surveillance, -3% (95% CI, -3 to -2) for Collaborative, and -5% (95% CI, -6 to -5) for Collaborative with Surveillance. The Collaborative with Surveillance intervention cluster had a substantial 46% reduction in AKI compared with Assistance alone (adjusted odds ratio=0.54; 0.40-0.74). CONCLUSIONS: This implementation trial estimates that the combination of Collaborative with Surveillance reduced the odds of AKI by 46% at VAMCs and is suggestive of a reduction among patients with CKD. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: IMPROVE AKI Cluster-Randomized Trial (IMPROVE-AKI), NCT03556293.

Iodinated Contrast Administration and Risks of Thyroid Dysfunction: A Retrospective Cohort Analysis of the U.S. Veterans Health Administration System.

Background: Iodine-induced thyroid dysfunction is a potential risk among susceptible individuals. Iodinated contrast media is a common source of an acute iodine load used in the health care setting and is frequently required for diagnostic computed tomography scans, coronary angiograms, and other radiologic studies. However, the epidemiologic risks of iodine-thyroid dysfunction have not been fully established in the United States. Methods: This population-based retrospective cohort study used the U.S. Veterans Health Administration database between 1998 and 2021 and included adults aged ≥18 years with a serum thyrotropin (TSH) measurement. Multivariable logistic regression was used to ascertain the risk of incident thyroid dysfunction (defined by repeated measurements of serum thyroid function) following iodine exposure, adjusting for age, sex, race/ethnicity, baseline serum TSH concentration, and duration between baseline and follow-up TSH concentration. Results: The cohort was composed of N = 4,253,119 veterans (mean ± SD = 63.5 ± 14.3 years; 92.9% men; 65.6% non-Hispanic Whites) with 8,729,155 corresponding pairs of serum TSH measurements, from which there were 499,897 TSH pairs with intervening iodine exposure. Thyroid dysfunction occurred in 4.8% of those pairs who had received iodine contrast and 3.6% of those without iodine exposure. Iodinated exposure was associated with an increased risk of thyroid dysfunction (odds ratio [OR] = 1.39, 95% confidence intervals [CI] = 1.37-1.41, p < 0.001) and consistent for all types of serum thyroid dysfunction (overt or subclinical hypo-/hyperthyroidism). Men were at higher risk for the development of thyroid dysfunction than women (men: OR = 1.42, 95% CI = 1.40-1.44; women: OR = 1.16, 95% CI = 1.11-1.21; p-for-interaction <0.001). Conclusions: In this largest analysis of U.S. adults to date, iodine exposure was associated with only clinically small absolute increased risks of thyroid dysfunction, particularly in men. These findings suggest that screening of thyroid function following iodinated contrast administration should be targeted to high-risk individuals.

Excess iodine exposure acutely increases salivary iodide and antimicrobial hypoiodous acid concentrations in humans.

The lactoperoxidase (LPO)-hydrogen peroxide-halides reaction (LPO system) converts iodide and thiocyanate (SCN-) into hypoiodous acid (HOI) and hypothiocyanite (OSCN-), respectively. Since this system has been implicated in defense of the airways and oropharynx from microbial invasion, in this proof-of-concept study we measured the concentrations of these analytes in human saliva from a convenience clinical sample of 40 qualifying subjects before and after acute iodine administration via the iodinated contrast medium used in coronary angiography to test the hypothesis that an iodide load increases salivary iodide and HOI concentrations. Saliva was collected and salivary iodide, SCN-, HOI and OSCN- were measured using standard methodology. The large iodine load delivered by the angiographic dye, several 100-fold in excess of the U.S. Recommended Daily Allowance for iodine (150 µg/day), significantly increased salivary iodide and HOI levels compared with baseline levels, whereas there was no significant change in salivary SCN- and OSCN- levels. Iodine load and changes of salivary iodide and HOI levels were positively correlated, suggesting that higher iodide in the circulation increases iodide output and salivary HOI production. This first of its kind study suggests that a sufficient but safe iodide supplementation less than the Tolerable Upper Limit for iodine set by the U.S. Institute of Medicine (1,100 µg/day) may augment the generation of antimicrobial HOI by the salivary LPO system in concentrations sufficient to at least in theory protect the host against susceptible airborne microbial pathogens, including enveloped viruses such as coronaviruses and influenza viruses.

Iodine contrast exposure and incident COVID-19 infection.

Background: Iodine and particularly its oxidated forms have long been recognized for its effective antiseptic properties. Limited in vitro and in vivo data suggest that iodine exposure may rapidly inactivate, reduce transmission, and reduce infectivity of SARS-CoV-2. We hypothesized that iodine exposure may be associated with decreased incident COVID-19 infection. Methods: A retrospective population-level cohort analysis was performed of the U.S. Veterans Health Administration between 1 March 2020 and 31 December 2020, before the widespread availability of vaccines against SARS-CoV-2. Multivariable logistic regression models estimated the adjusted odds ratios (OR) and 95% confidence intervals (CI) of the associations between iodinated contrast exposure and incident COVID-19 infection, adjusting for age, sex, race/ethnicity, place of residence, socioeconomic status, and insurance status. Results: 530,942 COVID-19 tests from 333,841 Veterans (mean ± SD age, 62.7 ± 15.2 years; 90.2% men; 61.9% non-Hispanic Whites) were analyzed, of whom 9% had received iodinated contrast ≤60 days of a COVID-19 test. Iodine exposure was associated with decreased incident COVID-19 test positivity (OR, 0.75 95% CI, 0.71-0.78). In stratified analyses, the associations between iodinated contrast use and decreased COVID-19 infection risk did not differ by age, sex, and race/ethnicity. Conclusion: Iodine exposure may be protective against incident COVID-19 infection. Weighed against the risks of supraphysiologic iodine intake, dietary, and supplemental iodine nutrition not to exceed its Tolerable Upper Limit may confer an antimicrobial benefit against SARS-CoV-2. A safe but antimicrobial level of iodine supplementation may be considered in susceptible individuals, particularly in geographic regions where effective COVID-19 vaccines are not yet readily available.

High rate of left ventricular hypertrophy on screening echocardiography among adults living with HIV in Malawi.

BACKGROUND: There are limited data on structural heart disease among people living with HIV in southern Africa, where the success of antiretroviral therapy (ART) has drastically improved life expectancy and where risk factors for cardiovascular disease are prevalent. METHODS: We performed a cross-sectional study of screening echocardiography among adults (≥18 years) with HIV in Malawi presenting for routine ART care. We used univariable and multivariable logistic regression to evaluate correlates of abnormal echocardiogram. RESULTS: A total of 202 individuals were enrolled with a median age of 45 years (IQR 39-52); 52% were female, and 27.7% were on antihypertensive medication. The most common clinically significant abnormality was left ventricular hypertrophy (LVH) (12.9%, n=26), and other serious structural heart lesions were rare (<2% with ejection fraction less than 40%, moderate-severe valve lesions or moderate-severe pericardial effusion). Characteristics associated with abnormal echocardiogram included older age (OR 1.04, 95% CI 1.01 to 1.08), higher body mass index (OR 1.09, 95% CI 1.02 to 1.17), higher mean systolic blood pressure (OR 1.03, 95% CI 1.02 to 1.05) and higher mean diastolic blood pressure (OR 1.03, 95% CI 1.01 to 1.05). In a multivariable model including age, duration on ART, body mass index, and systolic and diastolic blood pressure, only mean body mass index (adjusted OR 1.10, 95% CI 1.02 to 1.19), systolic blood pressure (aOR 1.05, 95% CI 1.03 to 1.08) and diastolic blood pressure (aOR 0.96, 95% CI 0.92 to 1.00) remained associated with abnormal echocardiogram. CONCLUSIONS: LVH was common in this population of adults on ART presenting for routine care and was associated with elevated blood pressure. Further research is needed to characterise the relationship between chronic hypertension, LVH and downstream consequences, such as diastolic dysfunction and heart failure in people living with HIV.

High Rates of Uncontrolled Blood Pressure in Malawian Adults Living with HIV and Hypertension.

Background: Hypertension is among the most commonly diagnosed non-communicable diseases in Africa, and studies have demonstrated a high prevalence of hypertension among individuals with HIV. Despite high prevalence, there has been limited attention on the clinical outcomes of hypertension treatment in this population. Objective: We sought to characterize rates of and factors associated with blood pressure control over one year among individuals on antiretroviral therapy (ART) and antihypertensive medications. Methods: We performed a prospective observational cohort study at an HIV clinic in Malawi. We defined uncontrolled hypertension as a systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure ≥90 mm Hg at two or more follow-up visits during the year, while controlled hypertension was defined as <140 mm Hg systolic and <90 mm Hg diastolic at all visits, or at all but one visit. We calculated an antihypertensive non-adherence score based on self-report of missed doses at each visit (higher score = worse adherence) and used rank sum and chi-square tests to compare sociodemographic and clinical factors (including adherence) associated with blood pressure control over the year. Results: At study entry, 158 participants (23.5%) were on antihypertensive medication; participants had a median age of 51.0 years, were 66.5% female, and had a median of 6.9 years on ART. 19.0% (n = 30) achieved blood pressure control over the year of follow-up. Self-reported non-adherence to hypertension medications was the only factor significantly associated with uncontrolled blood pressure. The average non-adherence score for those with controlled blood pressure was 0.22, and for those with uncontrolled blood pressure was 0.61 (p = 0.009). Conclusions: Adults living with HIV and hypertension in our cohort had low rates of blood pressure control over one year associated with self-reported non-adherence to antihypertensive medications. Given the high prevalence and incidence of hypertension, interventions to improve blood pressure control are needed to prevent associated long-term cardio- and cerebrovascular morbidity and mortality.

Ferumoxytol-enhanced magnetic resonance T1 reactivity for depiction of myocardial hypoperfusion.

Myocardial T1 reactivity, defined as the relative change in T1 between rest and vasodilator-induced stress, has been proposed as a magnetic resonance imaging (MRI) biomarker of tissue perfusion. We hypothesize that the superparamagnetic iron-oxide nanoparticle, ferumoxytol, sensitizes T1 to changes in the intramyocardial vascular compartment and improves the sensitivity and specificity of T1 reactivity as an imaging biomarker of tissue perfusion. We aim to assess the diagnostic performance of ferumoxytol-enhanced (FE) myocardial T1 reactivity in swine models of myocardial hypoperfusion. We induced acute myocardial hypoperfusion in 13 swine via percutaneous, transcatheter deployment of a 3D printed intracoronary stenosis implant into the left anterior descending coronary artery. We performed native and FE adenosine stress testing using 5(3)3(3)3 MOLLI and SASHA T1 mapping sequences with bSSFP readout on a clinical 3.0 T magnet. MOLLI T1 maps were fitted using both the conventional MOLLI and the Instantaneous Signal Loss (InSiL) T1-fitting algorithms. Regardless of the MOLLI or SASHA pulse sequence or T1-fitting algorithm, ferumoxytol contrast increased the dynamic range of T1 reactivity in both the remote and ischemic myocardial regions. Relative to remote myocardium, native and FE T1 reactivity were blunted in ischemic myocardium (p < 0.05) with InSiL-MOLLI, MOLLI and SASHA. An InSiL-MOLLI-derived FE T1 reactivity threshold of -4.65% had 73.3% sensitivity and 96.2% specificity for prediction of regional wall motion abnormalities (AUC 0.915, 95% CI 0.786-0.979), whereas a SASHA-derived FE T1 reactivity threshold of -5.25% had 75.0% sensitivity and 95.2% specificity (AUC 0.905, 95% CI 0.751-0.979). Ferumoxytol significantly increased the dynamic range of T1 reactivity as a measure of myocardial hypoperfusion in vasodilator stress T1 mapping studies. FE T1 reactivity maps can be used to quantitatively distinguish ischemic and remote myocardium with high specificity in swine models of acute myocardial hypoperfusion.

3D-Printed Coronary Implants Are Effective for Percutaneous Creation of Swine Models with Focal Coronary Stenosis.

Reliable, closed-chest methods for creating large animal models of acute myocardial hypoperfusion are limited. We demonstrated the feasibility and efficacy of using magnetic resonance (MR)-compatible 3D-printed coronary implants for establishing swine models of myocardial hypoperfusion. We designed, manufactured, and percutaneously deployed implants in 13 swine to selectively create focal coronary stenosis. To test the efficacy of the implants to cause hypoperfusion or ischemia in the perfused territory, we evaluated regional wall motion, myocardial perfusion, and infarction using MR imaging. The overall swine survival rate was 85% (11 of 13). The implant retrieval rate was 92% (12 of 13). Fluoroscopic angiography confirmed focal stenosis. Cine and perfusion MRI showed regional wall motion abnormalities and inducible ischemia, respectively. Late gadolinium enhancement and histopathology showed no myocardial infarction. Our minimally invasive technique has promising applications for validation of new diagnostic methods in cardiac MR. Graphical abstract Our new minimally invasive, percutaneous method for creating swine models of acute focal coronary stenosis can be used for magnetic resonance imaging studies of myocardial ischemia. Comparable to existing methods in its efficacy and reliability, this rapid prototyping technique will allow researchers to more easily conduct translational cardiac imaging studies of coronary artery disease in large animal models.

Novel Percutaneous Approach for Deployment of 3D Printed Coronary Stenosis Implants in Swine Models of Ischemic Heart Disease.

Minimally invasive methods for creating models of focal coronary narrowing in large animals are challenging. Rapid prototyping using three-dimensionally (3D) printed coronary implants can be employed to percutaneously create a focal coronary stenosis. However, reliable delivery of the implants can be difficult without the use of ancillary equipment. We describe the use of a mother-and-child coronary guide catheter for stabilization of the implant and for effective delivery of the 3D printed implant to any desired location along the length of the coronary vessel. The focal coronary narrowing was confirmed under coronary cineangiography and the functional significance of the coronary stenosis was assessed using gadolinium-enhanced first-pass cardiac perfusion MRI. We showed that reliable delivery of 3D printed coronary implants in swine models (n = 11) of ischemic heart disease can be achieved through repurposing mother-and-child coronary guide catheters. Our technique simplifies the percutaneous delivery of coronary implants to create closed-chest swine models of focal coronary artery stenosis and can be performed expeditiously, with a low procedural failure rate.

Usefulness and safety of percutaneous coronary interventions for cardiac transplant vasculopathy.

Late morbidity and death as a result of progressive coronary vascular obliteration remains a major unsolved problem after orthotopic heart transplantation. Various percutaneous catheter intervention (PCI) methods have been used to treat transplant coronary artery disease (CAD), but few reports have assessed the longitudinal results of these procedures. Of 1,440 cardiac transplant patients at University of California, Los Angeles, Medical Center, treated between 1984 and 2004, 65 patients who had undergone orthotopic heart transplantation underwent PCI on a total of 156 coronary artery lesions because of transplant CAD between July 1993 and August 2004. The procedural success rate was 93%. Angiographic follow-up was available for 42 patients and 101 lesions 9.5 +/- 5.8 months after PCI. The global restenosis rate was 36%. Multivariate analysis was used to assess 49 clinical, angiographic, and immunologic variables per lesion. The use of a cutting balloon increased the risk of restenosis (odds ratio 11.5, p <0.01) and the use of stents decreased the risk of restenosis (odds ratio 0.34, p <0.05) compared with other PCI methods. The restenosis rate with drug-eluting stents was 19%, lower than that with bare metal stents (31%). Of the 65 patients, 20 (31%) died within 1.9 +/- 1.8 years after PCI. The actuarial survival rate was 56% at 5 years after the first PCI. In conclusion, although the restenosis rate after PCI was higher than that in nontransplant patients with CAD, the immediate and long-term results were acceptable in this high-risk population. Despite the intense inflammation associated with transplant CAD, drug-eluting stents appeared to reduce the occurrence of restenosis. Compared with historical controls, PCI may also improve the actuarial survival rate of patients undergoing orthotopic heart transplantation.

Relation of metformin treatment to clinical events in diabetic patients undergoing percutaneous intervention.

Diabetic patients undergoing coronary interventions have worse clinical and angiographic outcomes than do patients without diabetes. Metformin, an insulin sensitizer, may decrease the occurrence of these outcomes. Diabetic patients in the Prevention of Restenosis with Tranilast and its Outcomes Trial were identified through their medical records (n = 2,772). In this trial, 1,110 diabetic patients received nonsensitizer therapy (insulin and/or sulfonylureas) and 887 received sensitizer therapy (metformin with or without additional therapy). Logistic regression was used to obtain odds ratios (ORs) (sensitizer vs nonsensitizer therapy) of any clinical event (death, myocardial infarction, or ischemia-driven target vessel revascularization) and adjusted for multiple risk factors. Multivariate analysis showed no effect of lesion characteristics on clinical outcomes. Compared with patients on nonsensitizer therapy, those on sensitizer therapy showed an adjusted OR of 0.72 (95% confidence interval [CI] 0.57 to 0.91, p = 0.005) for any clinical event. The differences between the nonsensitizer therapy group and the sensitizer group were attributable mainly to decreased rates of death (OR 0.39, 95% CI 0.19 to 0.77, p = 0.007) and myocardial infarction (OR 0.31, 95% CI 0.15 to 0.66, p = 0.002). In our retrospective analysis, use of metformin in diabetics undergoing coronary interventions appeared to decrease adverse clinical events, especially death and myocardial infarction, compared with diabetic patients treated with nonsensitizer therapy.

Intracoronary radiation to treat in-stent restenosis in six cardiac transplant patients.

Transplant vasculopathy significantly limits the survival of cardiac transplant patients and occurs in 50% of patients by 5 years posttransplant. We report our experience with six cardiac transplant patients who underwent intracoronary brachytherapy for in-stent restenosis. At four centers, six patients underwent intracoronary radiation for in-stent restenosis. All patients received extended antiplatelet therapy with clopidogrel and aspirin. Follow-up angiography was performed in all patients. Two of the six patients underwent subsequent target lesion revascularization. Patient 1 presented with total occlusion of her radiated lesion. She had a complex procedure requiring stenting for a dissection after the radiation dwell. Patient 2 had high-grade restenosis following brachytherapy. Patient 3 had a 50% restenotic lesion. Patients 4, 5, and 6 had follow-up angiography that showed no evidence of restenosis. There are few good options to treated accelerated transplant vasculopathy. Radiation therapy may be a viable option in this difficult patient population.

Cutting Balloon angioplasty for cardiac transplant vasculopathy.

We performed Cutting Balloon angioplasty on 20 lesions in 11 heart transplant recipients 7.5 +/- 3.8 years after transplantation. The mean percentage of diameter stenosis decreased from 88.3% +/- 13.8% to 19.6% +/- 13.7% after Cutting Balloon angioplasty without complication. Seven patients underwent follow-up angiography at 4.9 +/- 1.7 months in a total of 12 lesions, and all lesions showed restenosis with a mean diameter stenosis of 84.4% +/- 19.2%. Cutting Balloon angioplasty can be used to treat obstructions in cardiac transplant coronary arteries; however, it may cause exacerbation and produce a high restenosis rate.