Evolving consequences of right coronary artery to right atrium: coronary cameral fistula-a case report.

Background: Coronary cameral fistula is a rare diagnosis, which may be picked up incidentally on cardiac imaging. While majority of cases is asymptomatic, they can be complicated by myocardial ischaemia, arrhythmias, heart failure, infective endocarditis, and rarely rupture or thrombosis of the fistula leading to sudden death. Case summary: A 73-year-old female presents with fever, lethargy, and examination finding of a continuous cardiac murmur. CT coronary angiogram confirmed the presence of a coronary cameral fistula, with an aneurysmal RCA seen arising from the right coronary sinus, following an extensive tortuous course wrapping around the heart, and terminating at the right atrium. While there was initial streptococcus bacteraemia identified on blood culture sampling, no obvious masses were detected on the valves, chambers, or along the course of the fistula. Over time, she develops anginal chest pain and heart failure symptoms, with progressive dilatation of the right ventricle and functional tricuspid regurgitation secondary to shunting of the fistula into the right chambers. Surgical intervention was then pursued and successfully addressed these complications. Discussion: This case report highlights the importance of advanced imaging modalities for accurate diagnosis of coronary cameral fistulae, addressing late manifestations of the disease and the necessity for a collaborative, multidisciplinary approach in managing complex cardiac anomalies.

Post-Myocardial Infarction T-tubules Form Enlarged Branched Structures With Dysregulation of Junctophilin-2 and Bridging Integrator 1 (BIN-1).

BACKGROUND: Heart failure is a common secondary complication following a myocardial infarction (MI), characterized by impaired cardiac contraction and t-tubule (t-t) loss. However, post-MI nano-scale morphological changes to the remaining t-ts are poorly understood. METHOD AND RESULTS: We utilized a porcine model of MI, using a nonlethal microembolization method to generate controlled microinfarcts. Using serial block face scanning electron microscopy, we report that post-MI, after mild left-ventricular dysfunction has developed, t-ts are not only lost in the peri-infarct region, but also the remnant t-ts form enlarged, highly branched disordered structures, containing a dense intricate inner membrane. Biochemical and proteomics analyses showed that the calcium release channel, ryanodine receptor 2 (RyR2), abundance is unchanged, but junctophilin-2 (JP2), important for maintaining t-t trajectory, is depressed (-0.5×) in keeping with the t-ts being disorganized. However, immunolabeling shows that populations of RyR2 and JP2 remain associated with the remodeled t-ts. The bridging integrator 1 protein (BIN-1), a regulator of tubulogensis, is upregulated (+5.4×), consistent with an overdeveloped internal membrane system, a feature not present in control t-ts. Importantly, we have determined that t-ts, in the remote region, are narrowed and also contain dense membrane folds (BIN-1 is up-regulated +3.4×), whereas the t-ts have a radial organization comparable to control JP2 is upregulated +1.7×. CONCLUSIONS: This study reveals previously unidentified remodeling of the t-t nano-architecture in the post-MI heart that extends to the remote region. Our findings highlight that targeting JP2 may be beneficial for preserving the orientation of the t-ts, attenuating the development of hypocontractility post-MI.

Combined MSC and GLP-1 Therapy Modulates Collagen Remodeling and Apoptosis following Myocardial Infarction.

Background. Mesenchymal stem cells (MSCs) and glucagon-like peptide-1 (GLP-1) are being tested as treatment strategies for myocardial infarction (MI); however, their mechanisms in the heart are not fully understood. Methods. We examined the effects of MSCs, either native, or engineered to secrete a GLP-1 fusion protein (MSCs ± GLP-1), on human cardiomyocyte apoptosis in vitro. The effect on cardiac remodeling when encapsulated in alginate beads (CellBeads-MSC and CellBeads-MSC + GLP-1) was also evaluated in a pig MI model, whereby pigs were treated with Empty Beads, CellBeads-MSC, or CellBeads-MSC + GLP-1 and sacrificed at one or four weeks following MI. Results. MSC + GLP-1 conditioned media demonstrated antiapoptotic effects on ischaemic human cardiomyocytes in vitro. In vivo, qRT-PCR revealed large changes in the expression of several genes involved in extracellular matrix remodeling, which were altered following MSC ± GLP treatment. After four weeks, infarcted areas were imaged using atomic force microscopy, demonstrating significant alterations between groups in the structure of collagen fibrils and resulting scar. Conclusions. These data demonstrate that MSCs ± GLP-1 exhibit modulatory effects on healing post-MI, affecting both apoptosis and collagen scar formation. These data support the premise that both MSCs and GLP-1 could be beneficial in MI treatment.

Forward and back aspiration during ST-elevation myocardial infarction: a feasibility study.

AIMS: The inability to optimise stent expansion fully whilst simultaneously preventing distal embolisation during ST-elevation myocardial infarction (STEMI) remains a clinical conundrum. We aimed to describe a newly devised angiographic strategy of "forward" and "back" aspiration that leads to more complete thrombus removal and prevention of distal embolisation, to allow high-pressure post-dilatation of the implanted stent to be performed. METHODS AND RESULTS: Forward aspiration was conducted with a conventional aspiration thrombectomy catheter, with bail-out aspiration thrombectomy for angiographically persistent thrombus utilising the larger bore 6 Fr (0.056") guide catheter extension system (GuideLiner; Vascular Solutions, Inc., Minneapolis, MN, USA). Back aspiration was undertaken with a deeply intubated GuideLiner or guide catheter with a vacuum induced within, extending to the inflated angioplasty balloon, to allow for proximal embolic protection during balloon deflation during all stages of the PCI procedure, including high-pressure post-dilatation of the stent to the visually estimated reference vessel diameter (RVD). Over a six-month period 30 consecutive cases were undertaken during working hours. Bail-out GuideLiner-assisted aspiration thrombectomy was performed in 9/30 cases because of inadequate thrombus removal with a conventional aspiration thrombectomy catheter. Back aspiration was performed in all cases. In 27/30 cases high-pressure post-dilatation of the stent was performed. The mean maximum post-dilatation balloon size and mean proximal reference vessel diameter did not significantly differ (3.60±0.41 mm vs. 3.65±0.45 mm, p=0.68). In all cases, implantation +/- post-dilatation of the stent to the visually estimated RVD was achievable without any deterioration in TIMI blood flow or myocardial blush grade. CONCLUSIONS: The strategy of forward and back aspiration to facilitate stent implantation and high-pressure post-dilatation during STEMI appears to be safe and effective. Randomised controlled trials are required to confirm the safety and efficacy of this newly devised angiographic strategy.

Success, Safety, and Efficacy of the Mynx Femoral Closure Device in a Real-World Cohort: Single-Center Experience.

BACKGROUND: Femoral artery closure device use following percutaneous cannulation allows earlier mobilization, reduced staff burden, and improved comfort for patients compared with manual compression. The Mynx device (Access Closure, Inc), a novel extravascular closure device, uses a water-soluble non-thrombogenic polyethylene glycol plug. METHODS: We report retrospective analysis of success, complication rates, and associated factors in 432 consecutive patients undergoing elective outpatient coronary angiography in a single United Kingdom center. RESULTS: Six Fr sheaths were used in 62.1% and 5 Fr sheaths were used in 37.8%, with 100% successful deployment using a Mynx device. A total of 57.5% of patients were male. In 79.4%, this was the first procedure requiring femoral arteriotomy, while 20.6% had a previous procedure. Overall, 3.2% required conversion to manual compression/ FemoStop (St. Jude Medical) due to impending hematoma. In all, 99.5% of patients were discharged on the same day. Confirmed hematoma >5 cm was noted in 0.7% patients, with only 2 patients (0.5%) reporting "any discomfort" during deployment and the same requiring overnight hospitalization. Use of a 6 Fr sheath (compared with 5 Fr) was associated with conversion to manual compression and complications (P<.05), as was valvular heart disease as the indication for angiography (P<.05). Hematoma formation was associated with higher diastolic and mean arterial pressure (107.4 mm Hg vs 99.6 mm Hg; P<.01). There was no increase in complications associated with use of antiplatelet/anticoagulants, previous stroke, myocardial infarction/ischemic heart disease, peripheral vascular disease, diabetes, high body mass index, or previous angiographic procedure. CONCLUSIONS: Postangiography use of the Mynx closure device is highly successful, safe, and well-tolerated with a low complication rate, allowing safe same-day discharge.

Saphenous vein graft pseudoaneurysm: a case for medical management.

Saphenous vein bypass pseudoaneurysm is rare but fatal complication after coronary bypass surgery. Pseudoaneurysm is managed either with a surgical or percutaneous approach. This patient underwent quadruple coronary artery bypass grafting 10 years earlier and was referred for recurrence of angina. Coronary and graft angiography revealed a pseudoaneurysm in the saphenous vein graft supplying the intermediate coronary artery. After discussion with the cardiothoracic surgeons, the patient was managed conservatively. He was continued on Aspirin, beta-blockers, statins, nitrates and angiotensin converting enzyme inhibitors. He was followed-up regularly in outpatient clinic with a planned repeat coronary and graft angiography. The patient's symptoms remain stable and repeat angiography 24 months later did not show any significant deterioration of the graft pseudoaneurysm. He remains stable at 12 months after the repeated angiography.

NICE guidelines for new chest pain: comparison of new and old services.

In 2000 the National Service Framework for Coronary Artery Disease (CAD) prompted the development of rapid-access chest pain clinics (RACPCs). The aim of such clinics is to provide prompt assessment of chest pain to identify CAD with the use of an exercise tolerance test. In 2010, the National Institute for Health and Clinical Excellence (NICE) guidelines recommended using imaging studies based on CAD risk scoring and not an exercise tolerance test to exclude angina in patients with no previous history of known CAD. A comparison of the use of the 2010 NICE guidelines for the management of new-onset chest pain within a well-established exercise-based RACPC service is undocumented. The new recommendation moves the focus towards discharging low-risk patients, imaging studies/invasive procedure (angiogram) for the moderate-risk group and initiating anti-anginal treatment for the high-risk group. To phase the new recommendations into clinical practice in a district general hospital, the new guidelines were implemented in one out of three RACPC sessions per week. A retrospective assessment was carried out over a 4-month period to evaluate the new service implementation. A total of 160 patients attended the RACPC service, of which 56 (35%) were offered treatments according to the newer NICE guidelines and 104 (65%) were managed with the aim of exercising on the treadmill. This review gives an insight into the benefits of the new recommendations in practice, as well as highlighting some of the immediate limitations and barriers encountered.

Negative chronotropic effects and coronary ischaemic abnormalities following thalidomide therapy.

The severe teratogenic side effects of thalidomide led to its well-publicized withdrawal in the 1970s, but as it is cautiously being reintroduced into clinical use, new adverse effects are being described. A 65-year-old male with multiple myeloma received chemotherapy which included cyclophosphamide, thalidomide and dexamethasone. Whilst on this treatment he experienced severe chest pain leading to an acute hospital admission complicated by significant bradycardia with sinus pauses of 7 s, necessitating temporary right ventricular pacing. Despite correction of the bradycardia with temporary pacing, he experienced further episodes of chest pain, during which an ECG (with the pacemaker briefly switched off) showed ST elevation in the inferior leads along with runs of non-sustained ventricular tachycardia. Emergency coronary angiography demonstrated unobstructed coronary arteries. Due to ST elevation in the absence of flow-limiting coronary disease his presentation was presumed to be due to intermittent coronary artery spasm. He was started on sustained-release nifedipine without any beta-blockers and further thalidomide therapy was omitted. On this pharmacological therapy, over a period of 24 months, there were no further recurrences of any cardiac symptoms. To our knowledge there have been no previous reports of coronary artery spasm associated with the use of thalidomide. The precise mechanism remains undefined, with several plausible hypothetical pathways which we discuss. We discuss various mechanisms including autonomic, autocoid and paracrine modes of action that may underlie cardiac side effects of thalidomide. We report coronary spasm in addition to bradycardia as cardiac side effects that cardiologists and oncologists need to be alert to.

Encapsulated glucagon-like peptide-1-producing mesenchymal stem cells have a beneficial effect on failing pig hearts.

Stem cell therapy is an exciting and emerging treatment option to promote post-myocardial infarction (post-MI) healing; however, cell retention and efficacy in the heart remain problematic. Glucagon-like peptide-1 (GLP-1) is an incretin hormone with cardioprotective properties but a short half-life in vivo. The effects of prolonged GLP-1 delivery from stromal cells post-MI were evaluated in a porcine model. Human mesenchymal stem cells immortalized and engineered to produce a GLP-1 fusion protein were encapsulated in alginate (bead-GLP-1 MSC) and delivered to coronary artery branches. Control groups were cell-free beads and beads containing unmodified MSCs (bead-MSC), n = 4-5 per group. Echocardiography confirmed left ventricular (LV) dysfunction at time of delivery in all groups. Four weeks after intervention, only the bead-GLP-1 MSC group demonstrated LV function improvement toward baseline and showed decreased infarction area compared with controls. Histological analysis showed reduced inflammation and a trend toward reduced apoptosis in the infarct zone. Increased collagen but fewer myofibroblasts were observed in infarcts of the bead-GLP-1 MSC and bead-MSC groups, and significantly more vessels per mm(2) were noted in the infarct of the bead-GLP-1 MSC group. No differences were observed in myocyte cross-sectional area between groups. Post-MI delivery of GLP-1 encapsulated genetically modified MSCs provided a prolonged supply of GLP-1 and paracrine stem cell factors, which improved LV function and reduced epicardial infarct size. This was associated with increased angiogenesis and an altered remodeling response. Combined benefits of paracrine stem cell factors and GLP-1 were superior to those of stem cells alone. These results suggest that encapsulated genetically modified MSCs would be beneficial for recovery following MI.

Significance of exercise induced U wave inversion as a marker for coronary artery disease.

Exercise stress testing for detecting inducible ischaemia was first introduced in the 1950s and remained one of the only methods of stressing the heart for years to come. The presence of inducible ischaemia was assessed by ECG changes during exercise apart from other factors, namely, duration of exercise, blood pressure and heart rate response, metabolic equivalents achieved, etc. With the emergence of other tests to look for inducible ischaemia, for example, dobutamine stress echocardiography and myocardial perfusion scanning and also as the threshold for invasive evaluation has decreased, unusual and infrequently encountered ECG changes are not looked for during exercise stressing with the same degree of diligence. The authors describe below the case of a 49-year-old male whose left anterior descending artery stenosis was diagnosed on exercise stress test on the basis of a negative U wave.

Vascular endothelial growth factor (VEGF)-eluting stents: in vivo effects on thrombosis, endothelialization and intimal hyperplasia.

Local drug delivery by stent can reduce in-stent restenosis. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen. After stenting, the arterial wall is almost denuded of endothelium. This loss of endothelium contributes to the smooth muscle cell (SMC) proliferation seen in restenosis, since the endothelium actively inhibits SMC hyperplasia. Over time, the endothelium recovers and SMC hyperplasia is arrested. The capacity of VEGF-coated stents to accelerate re-endothelialization, and to therefore reduce restenosis and thrombosis, was tested in this study. Radiolabeled VEGF was absorbed onto stents and released over nine days in an in vitro perfusion circuit. VEGF-coated stents were deployed in arterial segments to study local tissue release. A New Zealand White rabbit iliac artery model for stent implantation was used. Re-endothelialization and thrombosis were assessed after seven days. Further animals were examined 28 days post-procedure for in-stent restenosis. Stented vessels were resin-embedded, sectioned and stained. Intimal thickening was calculated using computerized morphometry. In vitro, the stents released 80% of the initial load over nine days. At seven days, thrombus was significantly reduced (12.5 mg for controls versus 0 mg for VEGF; p = 0.014). No beneficial effect was seen on endothelialization, nor on intimal hyperplasia. Neointimal area was 2.2 0.9 mm2 for controls versus 2.4 1.8 mm2 for VEGF (p = 0.8). These VEGF-eluting stents do not accelerate re-endothelialization or inhibit restenosis. Stent thrombosis appears to be reduced, which may make these stents less thrombogenic and be valuable in higher-risk cases.

Angiopeptin-eluting stents: observations in human vessels and pig coronary arteries.

Local drug delivery from polymer-coated coronary stents may reduce the incidence of in-stent restenosis. Angiopeptin, an inhibitor of smooth muscle cell proliferation, may reduce the clinical impact of restenosis. The objectives of this study were to characterize the release kinetics and distribution of angiopeptin-loaded phosphorylcholine (PC)-coated drug delivery (DD) BiodivYsio stents and assess their safety and efficacy at reducing neointima formation. I125-angiopeptin-loaded DD-PC-coated stents were implanted into human saphenous vein segments ex vivo, and I125 angiopeptin was detected in the medial layer at 1 hour. When implanted in pig coronary arteries, I125 angiopeptin was found adjacent to the stent at intervals up to 28 days. No significant amounts were found elsewhere. To assess efficacy, twelve angiopeptin-loaded DD-PC-coated stents, twelve non-loaded DD-PC stents, ten standard PC-coated stents and 8 uncoated stents were implanted into normal porcine coronary arteries. Stents were harvested at 28 days and neointima formation was assessed by computerized morphometry. No adverse tissue reactions were seen with any of the PC-coated stents. No significant differences were seen in neointimal or luminal cross-sectional areas between study groups. Local delivery of I125 angiopeptin into the vascular wall can be achieved using a PC-coated stent. Delivery of angiopeptin from drug delivery PC-coated stents is safe, but does not lead to a significant reduction in neointimal growth at 28 days within the parameters of this study.