Project description:Hypothermia may attenuate reperfusion injury and thereby improve acute myocardial infarction therapy. Systemic cooling trials failed to reduce infarct size, perhaps because the target temperature was not reached fast enough. The use of selective intracoronary hypothermia combined with intracoronary temperature monitoring allows for titrating to target temperature and optimizing the cooling rate. We aimed to the test the feasibility of intracoronary cooling for controlled, selective myocardial hypothermia in an isolated beating pig heart. In five porcine hearts the left anterior descending artery (LAD) was occluded by an over-the-wire balloon (OTWB). After occlusion, saline at 22°C was infused through the OTWB lumen for 5 minutes into the infarct area at a rate of 30 ml/min. Thereafter the balloon was deflated but infusion continued with saline at 4°C for 5 minutes. Distal coronary temperature was continuously monitored by a pressure/temperature guidewire. Myocardial temperature at several locations in the infarct and control areas was recorded using needle thermistors. In the occlusion phase, coronary temperature decreased by 11.4°C (range 9.4-12.5°C). Myocardial temperature throughout the infarct area decreased by 5.1°C (range 1.8-8.1°C) within three minutes. During the reperfusion phase, coronary temperature decreased by 6.2°C (range 4.1-10.3°C) and myocardial temperature decreased by 4.5°C (range 1.5-7.4°C). Myocardial temperature outside the infarct area was not affected. In the isolated beating pig heart with acute occlusion of the LAD, we were able to rapidly "induce, maintain, and control" a stable intracoronary and myocardial target temperature of at least 4°C below body temperature without side effects and using standard PCI equipment, justifying further studies of this technique in humans.
Project description:BackgroundTreating acute myocardial infarction in the setting of insignificant coronary obstruction is an emerging challenge especially with the application of intracoronary imaging like intravascular ultrasound and optical coherence tomography (OCT). The cardiologists dealing with such patients may consider not to stent if there is intracoronary imaging evidence of minimal thrombus without plaque rupture and the vessel appears patent with settling of chest pain and electrocardiogram (ECG) changes.Case summaryA 47-year-old gentleman presented direct to the emergency department after experiencing retrosternal chest pain with an ECG showing hyperacute anterior T waves. He had ongoing chest pain and was therefore brought to the cardiac cath lab on the primary percutaneous coronary intervention (PCI) pathway. The first picture showed that the proximal left anterior descending (LAD) was occluded (TIMI 0 flow) with evidence of large thrombus burden. Pre-dilating with a 2.5 × 15 mm balloon did not change flow. Aspiration with an Export catheter was carried out for several runs. Most of the thrombus was successfully removed; however, some of it did go into the distal LAD but was successfully retrieved with aspiration catheter. The diagonal branch was occluded with thrombus which was wired followed by thrombus aspiration establishing TIMI II flow. The procedure was covered with Eptifibatide boluses and heparin. After thrombectomy, angiographically there was no obvious lesion present within the LAD. Optical coherence tomography confirmed only mild atheroma with a small amount of plaque and minimal thrombus. There was OCT evidence of plaque erosion without any plaque rupture. The area was above 9 mm2 and we decided not to treat that with a stent. The right coronary artery had an anterior take-off and was unobstructed. In conclusion, the patient had successful primary PCI to LAD with thrombus aspiration and balloon angioplasty only. He was placed on 12 months of dual antiplatelets therapy with Aspirin and Prasugrel.DiscussionThis case highlights the rare presentation of patients with acute myocardial infarction with plaque erosion and the usefulness of OCT in formulating a management plan.
Project description:BackgroundMyocardial perfusion imaging (MPI) using single-photon emission computed tomography (SPECT) can in general be used safely in daily clinical practice. However, under the right circumstances, it can lead to serious complications.Case summaryA 68-year-old female patient with diabetes and a history of inferior ST-elevation myocardial infarction 8 years earlier, visited our outpatient clinic with atypical chest discomfort. In order to assess whether this is due to myocardial ischaemia, MPI-SPECT was ordered. As it was suspected she would not achieve sufficient exercise levels, pharmacologic stress using adenosine was arranged. During the scan, she developed acute myocardial infarction. Subsequent urgent coronary angiography demonstrated a subtotal stenosis in the proximal left anterior descending coronary artery which was successfully stented. She was still free from angina 4 months later.DiscussionThe combination of a reduced systemic and coronary perfusion pressure in the presence of an exhausted coronary autoregulation, may be a starting point for local geometrical changes that initiate the classic cascade of thrombus formation and acute occlusion of coronary arteries during MPI-SPECT. This illustrates the need for continuous patient and electrocardiogram monitoring.
Project description:BackgroundVentricular septal rupture (VSR), a mechanical complication following an acute myocardial infarction (MI), is thought to result from coagulation necrosis due to lack of collateral reperfusion. Although the gold standard test to confirm left-to-right shunting between ventricular cavities remains invasive ventriculography, two-dimensional transthoracic echocardiography (TTE) with color flow Doppler and cardiac MRI (CMR) are reliable tests for the non-invasive diagnosis of VSR.Case presentationA 62-year-old Caucasian female presented with a late case of a VSR post inferior MI diagnosed by multimodality cardiac imaging including TTE, CMR and ventriculography.ConclusionWe review the presentation, diagnosis and management of VSR post MI.
Project description:BackgroundTakayasu arteritis is a chronic vasculitis of unknown aetiology primarily affecting medium to large arteries, particularly the aorta and arch vessels, and is predominantly seen in younger patients. Coronary artery involvement has been reported in 10-45% of autopsy cases, but isolated coronary Takayasu arteritis is extremely rare.Case summaryThis case report describes the course of a previously healthy 22-year-old woman who suffered an acute myocardial infarction complicated by cardiogenic shock requiring temporary mechanical support subsequently urgent heart transplantation. The patient was bridged to transplant by the use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO). The explanted heart showed evidence of Takayasu arteritis in the left coronary artery.DiscussionThe case illustrates the importance of VA-ECMO treatment for cardiogenic shock, the importance of the Scandiatransplant collaboration for urgent organ allocation and the diagnostic difficulties associated with Takayasu arteritis.
Project description:We present a case detailing the diagnostic challenges of a 23-year-old male presenting with a sudden severe headache, nausea, vomiting, and chest heaviness. Initial evaluation showed elevated blood pressure and respiratory rate. An emergency electrocardiogram (ECG) indicated ST-segment elevation myocardial infarction (STEMI), leading to immediate referral for percutaneous coronary intervention, which revealed normal coronary arteries. Further investigations identified a cisternal subarachnoid haemorrhage (SAH) on CT brain imaging. Despite multidisciplinary management, the patient's condition rapidly deteriorated, resulting in cardiac arrest and mortality. Our case highlights the importance of thorough evaluation and multidisciplinary collaboration in managing complex presentations, emphasizing vigilance in recognizing and managing concurrent pathologies in young patients with acute symptoms.
Project description:BackgroundIsolated right ventricular myocardial infarction (RVMI) due to a recessive right coronary artery (RCA) occlusion is a rare presentation. It is typically caused by right ventricle (RV) branch occlusion complicating percutaneous coronary intervention. We report a case of an isolated RVMI due to flush RCA occlusion presenting via our primary percutaneous coronary intervention ST-elevation myocardial infarction pathway.Case summaryA 61-year-old female smoker with a history of hypercholesterolaemia presented via the primary percutaneous coronary intervention pathway with sudden onset of shortness of breath, dizziness, and chest pain while walking. Transradial coronary angiography revealed a normal left main coronary artery, large left anterior descending artery that wrapped around the apex and dominant left circumflex artery with the non-obstructive disease. The RCA was not selectively entered despite multiple attempts. The left ventriculogram showed normal left ventricle (LV) systolic function. She was in cardiogenic shock with a persistent ectopic atrial rhythm with retrograde p-waves and stabilized with intravenous dobutamine thus avoiding the need for a transcutaneous venous pacing system. A computed tomography pulmonary angiogram demonstrated no evidence of pulmonary embolism while an urgent cardiac gated computed tomography revealed a recessive RCA with ostial occlusive lesion. A cardiac magnetic resonance imaging confirmed RV free wall infarction. She was managed conservatively and discharged to her local district general hospital after 5th day of hospitalization at the tertiary centre.DiscussionThis case describes a relatively rare myocardial infarction presentation that can present with many disease mimics which can require as in this case, a multi-modality imaging approach to establish the diagnosis.
Project description:Although heart failure following myocardial infarction (MI) represents a major health burden, underlying microstructural and functional changes remain incompletely understood. Here, we report on a case of unexpected MI after treatment with the catecholamine isoproterenol in an experimental imaging study in mice using different state-of-the-art imaging modalities. The decline in cardiac function was documented by ultrahigh-frequency echocardiography and speckle-tracking analyses. Myocardial microstructure was studied ex vivo at a spatial resolution of 100 × 100 × 100 μm3 using diffusion tensor magnetic resonance imaging (DT-MRI) and histopathologic analyses. Two weeks after ISO treatment, the animal showed an apical aneurysm accompanied by reduced radial strain in corresponding segments and impaired global systolic function. DT-MRI revealed a loss of contractile fiber tracts together with a disarray of remaining fibers as corresponding microstructural correlates. This preclinical case report provides valuable insights into pathophysiology and morphologic-functional relations of heart failure following MI using emerging imaging technologies.
Project description:BackgroundCardiosphere-derived cells (CDCs) reduce scarring after myocardial infarction, increase viable myocardium, and boost cardiac function in preclinical models. We aimed to assess safety of such an approach in patients with left ventricular dysfunction after myocardial infarction.MethodsIn the prospective, randomised CArdiosphere-Derived aUtologous stem CElls to reverse ventricUlar dySfunction (CADUCEUS) trial, we enrolled patients 2-4 weeks after myocardial infarction (with left ventricular ejection fraction of 25-45%) at two medical centres in the USA. An independent data coordinating centre randomly allocated patients in a 2:1 ratio to receive CDCs or standard care. For patients assigned to receive CDCs, autologous cells grown from endomyocardial biopsy specimens were infused into the infarct-related artery 1·5-3 months after myocardial infarction. The primary endpoint was proportion of patients at 6 months who died due to ventricular tachycardia, ventricular fibrillation, or sudden unexpected death, or had myocardial infarction after cell infusion, new cardiac tumour formation on MRI, or a major adverse cardiac event (MACE; composite of death and hospital admission for heart failure or non-fatal recurrent myocardial infarction). We also assessed preliminary efficacy endpoints on MRI by 6 months. Data analysers were masked to group assignment. This study is registered with ClinicalTrials.gov, NCT00893360.FindingsBetween May 5, 2009, and Dec 16, 2010, we randomly allocated 31 eligible participants of whom 25 were included in a per-protocol analysis (17 to CDC group and eight to standard of care). Mean baseline left ventricular ejection fraction (LVEF) was 39% (SD 12) and scar occupied 24% (10) of left ventricular mass. Biopsy samples yielded prescribed cell doses within 36 days (SD 6). No complications were reported within 24 h of CDC infusion. By 6 months, no patients had died, developed cardiac tumours, or MACE in either group. Four patients (24%) in the CDC group had serious adverse events compared with one control (13%; p=1·00). Compared with controls at 6 months, MRI analysis of patients treated with CDCs showed reductions in scar mass (p=0·001), increases in viable heart mass (p=0·01) and regional contractility (p=0·02), and regional systolic wall thickening (p=0·015). However, changes in end-diastolic volume, end-systolic volume, and LVEF did not differ between groups by 6 months.InterpretationWe show intracoronary infusion of autologous CDCs after myocardial infarction is safe, warranting the expansion of such therapy to phase 2 study. The unprecedented increases we noted in viable myocardium, which are consistent with therapeutic regeneration, merit further assessment of clinical outcomes.FundingUS National Heart, Lung and Blood Institute and Cedars-Sinai Board of Governors Heart Stem Cell Center.
Project description:A 42-year-old female was hospitalized with 2-day history of fever, dyspnea, and chest tightness. Four years ago, she had similar symptoms at the eighth week of gestation. Computed tomography coronary angiography only suggested moderate stenosis, but cardiac MRI indicated myocardial infarction. The coronary angiography demonstrated a woven coronary artery. She underwent successful coronary artery bypass grafting surgery and took medication regularly. Finally, the prognosis was favorable. Cardiovascular events seldom happen in fertile women because of the protection of estrogen, but once it occurs, the potential cause, such as coronary anomaly and other risk factors, should not be overlooked.