Fractional myocardial blood volume by ferumoxytol-enhanced MRI: Estimation of ischemic burden.

PURPOSE: To investigate model-fitted fractional myocardial blood volume (fMBV) derived from ferumoxytol-enhanced MRI as a measure of myocardial tissue hypoperfusion at rest. METHODS: We artificially induced moderate to severe focal coronary stenosis in the left anterior descending artery of 19 swine by percutaneous delivery of a 3D-printed coronary implant. Using the MOLLI pulse sequence, we acquired T1 maps at 3 T after multiple incremental ferumoxytol doses (0.0-4.0 mg/kg). We computed pixel-wise fMBV using a multi-compartmental modeling approach in 19 ischemic swine and 4 healthy swine. RESULTS: Ischemic myocardial segments showed a mean MRI-fMBV of 11.72 ± 3.00%, compared with 8.23 ± 2.12% in remote segments and 8.38 ± 2.23% in normal segments. Ischemic segments showed a restricted transvascular water-exchange rate (ki  = 15.32 ± 8.69 s-1 ) relative to remote segments (ki  = 17.78 [11.60, 26.36] s-1 ). A mixed-effects model found significant difference in fMBV (p = 0.002) and water-exchange rate (p < 0.001) between ischemic and remote myocardial regions after adjusting for biological sex and slice location. Analysis of fMBV as a predictor of impaired myocardial contractility using receiver operating characteristics showed an area under the curve of 0.89 (95% confidence interval [CI] 0.80, 0.95). An MRI-fMBV threshold of 9.60% has a specificity of 90.0% (95% CI 76.3, 97.2) and a sensitivity of 72.5% (95% CI 56.1, 83.4) for prediction of impaired myocardial contractility. CONCLUSIONS: Model-fitted fMBV derived from ferumoxytol-enhanced MRI can distinguish regions of ischemia from remote myocardium in a swine model of myocardial hypoperfusion.

Characteristics and outcomes of patients presenting with acute myocardial infarction and cardiogenic shock during COVID-19.

OBJECTIVES: To evaluate characteristics and outcomes of patients presenting with acute myocardial infarction and cardiogenic shock (AMICS) during the coronavirus disease 2019 (COVID-19) pandemic. BACKGROUND: The COVID-19 pandemic has created challenges in delivering acute cardiovascular care. Quality measures and outcomes of patients presenting with AMICS during COVID-19 in the United States have not been well described. METHODS: We identified 406 patients from the National Cardiogenic Shock Initiative (NCSI) with AMICS and divided them into those presenting before (N = 346, 5/9/2016-2/29/2020) and those presenting during the COVID-19 pandemic (N = 60, 3/1/2020-11/10/2020). We compared baseline clinical data, admission characteristics, and outcomes. RESULTS: The median age of the cohort was 64 years, and 23.7% of the group was female. There were no significant differences in age, sex, and medical comorbidities between the two groups. Patients presenting during the pandemic were less likely to be Black compared to those presenting prior. Median door to balloon (90 vs. 88 min, p = 0.38), door to support (88 vs. 78 min, p = 0.13), and the onset of shock to support (74 vs. 62 min, p = 0.15) times were not significantly different between the two groups. Patients presented with ST-elevation myocardial infarction more often during the COVID-19 period (95.0% vs. 80.0%, p = 0.005). In adjusted logistic regression models, COVID-19 period did not significantly associate with survival to discharge (odds ratio [OR] 1.09, 95% confidence interval [CI] 0.54-2.19, p = 0.81) or with 1-month survival (OR 0.82, 95% CI 0.42-1.61, p = 0.56). CONCLUSIONS: Care of patients presenting with AMICS has remained robust among hospitals participating in the NCSI during the COVID-19 pandemic.

Single versus double Perclose techniques for vascular closure during transfemoral transcatheter aortic valve replacement.

INTRODUCTION: The preferred approach for transcatheter aortic valve replacement (TAVR) is transfemoral. There has been widespread adoption of the Perclose ProglideTM device for vascular closure. Typically, two devices are deployed before upsizing the access sheath in the "preclose technique." Prior investigations have compared the use of a single device versus double device technique, but none have shown significant clinical benefit to either approach. METHODS: Five hundred and six patients underwent transfemoral TAVR (TF-TAVR) with single or double Perclose devices for vascular closure from July 2015 to February 2020. A retrospective review was conducted, and propensity-matched analyses were used to account for differences in baseline characteristics. RESULTS: In the matched analysis, there were 251 patients in the single Perclose group and 238 in the double. There was a statistically significant improvement in overall procedural success using the single closure device (94.6% vs. 88.5%, p = 0.009) This was defined as intraprocedural hemostatic control, lack of contrast extravasation, arterial dissection, occlusion, or stenosis >50% in the final crossover angiogram, as well as unimpaired limb perfusion without claudication throughout the index hospitalization. There was also a significant improvement in arterial dissection rates (0.6% vs. 4.6%, p = 0.004), stenosis >50% (1.3% vs. 4.4%, p = 0.028), and Valve Academic Research Consortium major vascular complications (1.8% vs. 4.9%, p = 0.038). CONCLUSION: A single Perclose device is a safe means of vascular closure during TF-TAVR and may have important clinical benefits compared to the commonly used two-device technique.

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.

Acquired Long QT Syndrome after Acute Myocardial Infarction: A Rare but Potentially Fatal Entity.

Acquired long QT syndrome is typically caused by medications, electrolyte disturbances, bradycardia, or catastrophic central nervous system events. We report a case of myocardial infarction-related acquired long QT syndrome in a 58-year-old woman that had no clear cause and progressed to torsades de pointes requiring treatment with isoproterenol and magnesium. Despite negative results of DNA testing against a known panel of genetic mutations and polymorphisms associated with long QT syndrome, the patient's family history of fatal cardiac disease suggests a predisposing genetic component. This report serves to remind clinicians of this potentially fatal ventricular arrhythmia after myocardial infarction.

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.

Assessment of Sex Differences in 5-Year Clinical Outcomes Following Endovascular Revascularization for Peripheral Artery Disease.

Percutaneous transluminal angioplasty (PTA) is an effective treatment strategy for peripheral artery disease (PAD). Data are limiting regarding sex differences in patients with PAD who underwent PTA. We assessed the sex-related differences on 5-year clinical outcomes in patients with PAD who underwent PTA. We prospectively evaluated 765 patients with PAD (596 males and 169 females) who underwent PTA. We performed propensity score matching (PSM) analysis to adjust for any potential confounders. The primary endpoints were 5-year major adverse cardiac and cerebrovascular events (MACE) and major adverse lower-limb events (MALE) assessed by Kaplan-Meier curved analysis and log rank test. After PSM analysis, baseline clinical characteristics were similar in male and female patients. There was a trend toward a higher rate of major hematoma in female patients (6.1% vs. 0.9%, p = 0.066) and a lower rate of below the ankle amputation (24.7% vs. 16.5%, p = 0.097). During the 5-year clinical follow-up, male and female patients had similar rates of MACE (14.9% vs. 15.8%, log rank p = 0.838) and MALE (34.8% vs. 28.2%, log rank p = 0.264) as well as the individual endpoints. In subgroup analysis adjusted by PSM, female patients had a higher risk of bleeding complications in age ≥ 65 years, hypertension, diabetes mellitus, chronic kidney disease, and in the non-critical limb ischemia patients. Of patients with preserved renal function, female patients had a higher risk of MALE as compared to males. In conclusion, female patients with PAD who underwent PTA showed similar 5-year MACE and MALE compared with male patients.

Influenza A (H3N2) Induced Fulminant Myocarditis Requiring Mechanical Circulatory Support.

The authors report a case of fulminant myocarditis from an influenza A (H3N2) infection in a healthy individual who experienced cardiac arrest requiring extracorporeal membrane oxygenation (ECMO). The case highlights the management of complications arising from the use of ECMO including differential hypoxia and left ventricular overload requiring left ventricular venting. (Level of Difficulty: Beginner.).

Acute procedural outcomes of orbital atherectomy for the treatment of iliac artery disease: Sub-analysis of the CONFIRM registries.

Endovascular intervention is an appealing revascularization strategy for iliac artery disease. Atherectomy of the iliac artery is uncommon due to the risk of life-threatening perforation but may be necessary if the iliac lesion is heavily calcified, preventing stent delivery or optimal expansion. We assessed the feasibility and safety of orbital atherectomy for the treatment of iliac artery disease. Demographic data, lesion characteristics, and procedure outcomes for the CONFIRM patients with at least one iliac artery lesion treated with orbital atherectomy (n=62 patients; n=68 lesions) were compared to patients with at least one superficial femoral artery (SFA) lesion treated with orbital atherectomy (n=1570 patients; n=1809 lesions). The procedural complication rate, defined as the composite of flow limiting dissection, perforation, slow flow, vessel closure, spasm, embolism, or thrombosis, was compared in iliac lesions versus SFA lesions. The iliac artery group had more patients with diabetes, shorter lesions, and more severely calcified lesions. The orbital atherectomy run time was significantly shorter in the iliac artery group. Additionally, in the iliac group there was one reported perforation and one reported vessel closure; the rates of slow flow, spasm, embolism, thrombus, and flow limiting dissection were 0%. The overall procedural complication rate was significantly lower in the iliac group (2.9% vs. 11.2%, p=0.03). Orbital atherectomy of the iliac artery is feasible with few reported angiographic complications and compared favorably with the SFA group. Orbital atherectomy may be considered to facilitate the delivery and expansion of a balloon or stent if the iliac artery is calcified.

One-Year Outcomes of Orbital Atherectomy of Long, Diffusely Calcified Coronary Artery Lesions.

OBJECTIVES: The aim of this study was to determine the clinical outcomes of patients with long, diffusely calcified coronary artery lesions who underwent orbital atherectomy. BACKGROUND: The presence of severe coronary artery calcification increases the complexity of percutaneous coronary intervention. Orbital atherectomy of long, diffusely calcified lesions may increase the risk of periprocedural angiographic complications. Furthermore, the rate of ischemic complications, including target-vessel revascularization (TVR), in these long, calcified lesions is historically high. METHODS: In this retrospective multicenter registry, which included 458 real-world patients who underwent orbital atherectomy, a total of 154 patients (33.6%) required a total stent length of ≥50 mm (long-stent group). The primary endpoint was the 1-year major adverse cardiac and cerebrovascular event (MACCE) rate, defined as the composite of death, myocardial infarction, TVR, and stroke. RESULTS: The long stent group had a higher rate of perforation (1.9% vs 0.0%; P=.01) and dissection (2.6% vs 0.0%; P<.01). The primary endpoint was similar in the long and short groups (14.2% vs 11.5%, respectively; P=.40), as were the 1-year rates of death (2.6% vs 4.6%, respectively; P=.30), myocardial infarction (1.9% vs 1.6%, respectively; P=.80), TVR (9.7% vs 6.3%, respectively; P=.18), and stroke (1.3% vs 1.3%, respectively; P>.90). The stent thrombosis rate was similar in both groups (1.3% vs 1.3%; P>.90). CONCLUSIONS: Despite the higher angiographic complication rates, orbital atherectomy of long, diffusely calcified lesions was associated with acceptable rates of ischemic complications in this challenging lesion subset at 1-year follow-up.

Acute Procedural Outcomes of Orbital Atherectomy for the Treatment of Profunda Femoris Artery Disease: Subanalysis of the CONFIRM Registries.

OBJECTIVES: We compared the angiographic outcomes of patients treated with orbital atherectomy for profunda femoris artery (PFA) and superficial femoral artery (SFA) disease from the CONFIRM I-III registries. BACKGROUND: Endovascular revascularization of the PFA is considered a high-risk procedure given that it is an important collateral vessel when the SFA becomes occluded. Data on outcomes of endovascular revascularization of calcified PFA disease are limited. METHODS: The treatment of PFA disease with orbital atherectomy has not been previously reported. Patient demographics, lesion characteristics, and procedure data for all CONFIRM patients with at least one PFA lesion location (n = 33 patients; n = 33 lesions) were compared to patients with at least one SFA lesion location (n = 1574 patients; n = 1811 lesions). The primary endpoint was angiographic complication, defined as the composite of flow-limiting dissection, perforation, slow flow, vessel closure, spasm, embolism, or thrombosis. RESULTS: The PFA group had a shorter lesion length, larger residual stenosis, shorter total run time, and shorter inflation time. Adjunctive stenting was only performed in the SFA group (10%); no patient in the PFA group underwent stenting. The primary endpoint was low in the PFA group and compared favorably with the SFA group (3% vs 11%; P=.15). One patient in the PFA group had vessel spasm, while no patients had flow-limiting dissection, perforation, slow flow, vessel closure, embolism, or thrombus. CONCLUSIONS: Orbital atherectomy of the PFA was feasible and safe. A randomized trial is needed to determine the ideal treatment strategy for calcified PFA disease.

Outcomes of Patients With a History of Coronary Artery Bypass Grafting Who Underwent Orbital Atherectomy for Severe Coronary Artery Calcification.

OBJECTIVE: We assess the angiographic and clinical outcomes of patients with a history of coronary artery bypass graft (CABG) surgery who underwent orbital atherectomy for the treatment of severely calcified coronary lesions. BACKGROUND: The presence of severe coronary artery calcification (CAC) increases the complexity of percutaneous coronary intervention (PCI) and is associated with worse clinical outcomes. Patients with a history of CABG who undergo PCI often have comorbidities and are at higher risk for ischemic complications. METHODS: Of the 458 patients who underwent orbital atherectomy, 77 patients (17%) had a history of CABG and 381 (83%) did not. The primary endpoint was rate of 30-day major adverse cardiac and cerebrovascular events (MACCE), comprised of cardiac death, myocardial infarction (MI), target-vessel revascularization (TVR), and stroke. RESULTS: The CABG group had a higher prevalence of hypertension, chronic renal insufficiency, history of PCI, and unstable angina. The primary endpoint was similar in the CABG and non-CABG groups (1% vs 2%; P=.56), as were the individual endpoints of cardiac death (0% vs 2%; P=.27), MI (1% vs 1%; P=.85), TVR (0% vs 0%; P>.99), and stroke (0% vs 0%; P=.65). The rates of angiographic complications and stent thrombosis were similarly low in both groups. CONCLUSION: Despite a higher-risk baseline profile, patients with a history of CABG had similar angiographic and clinical outcomes compared with patients who had no previous history of CABG. Further studies are needed to clarify the role of orbital atherectomy in these patients.

Comparison of Heparin and Bivalirudin in Patients Undergoing Orbital Atherectomy.

OBJECTIVE: We compared the angiographic and clinical outcomes of heparin and bivalirudin in patients who underwent orbital atherectomy for severely calcified coronary lesions. BACKGROUND: Severely calcified coronary lesions are associated with increased ischemic complications. Orbital atherectomy modifies calcified plaque, thereby facilitating stent delivery and stent expansion. The ideal antithrombotic agent during orbital atherectomy is unknown. Previous studies reported that bivalirudin was associated with lower bleeding rates compared with heparin plus glycoprotein IIb/IIa inhibitors during percutaneous coronary intervention. METHODS: This retrospective multicenter analysis included 458 consecutive real-world patients with severely calcified coronary arteries who underwent orbital atherectomy. Patients were stratified based on the antithrombotic agent that was used. The primary safety endpoint was the 30-day rate of major adverse cardiac and cerebrovascular events, defined as death, myocardial infarction, target-vessel revascularization, and stroke. RESULTS: Heparin was used in 356/458 cases (77.2%) and bivalirudin was used in 102/458 cases (22.8%). The primary endpoint was similar in the heparin and bivalirudin groups (2% vs 3%; P=.55), as were the 30-day rates of death (1% vs 2%; P=.51), myocardial infarction (1% vs 1%; P=.90), target-vessel revascularization (0% vs 0%; P>.99), and stroke (0% vs 0%; P=.59). Angiographic complication, stent thrombosis, and major bleeding complication rates were similarly low in both groups. CONCLUSION: Both heparin and bivalirudin were safe and effective antithrombotic agents for patients who underwent orbital atherectomy. A randomized trial is needed to determine the antithrombotic agent of choice for orbital atherectomy.

Rapidly Progressing Chagas Cardiomyopathy.

Chagas disease, caused by the parasite Trypanosoma cruzi, can cause a potentially life-threatening cardiomyopathy in approximately 10-40% of afflicted individuals. The decline in cardiac function characteristically progresses over the course of many years. We report a case of Chagas disease in which the patient experienced an atypical rapid deterioration to severe cardiomyopathy over the course of 16 months. This case argues the need for increased routine surveillance for patients with confirmed T. cruzi infection, who are determined to be at high-risk for worsening cardiomyopathy.