Intra-isthmus re-entry, in which the tachycardia circuit is localized within the cavotricuspid isthmus region and the coronary sinus ostium, has been reported as an atypical form of atrial tachycardia. It has been delineated by three-dimensional mapping as either macro-re-entrant type around the cavotricuspid isthmus and coronary sinus area (but with the coexistence of typical atrial flutter), or focal type from the cavotricuspid isthmus area.

We report the case of a previously healthy 10-year-old girl who experienced sudden cardiac arrest during a cross-country event. Prompt bystander cardiopulmonary resuscitation was initiated and continued until ambulance arrival. The initial rhythm was polymorphic ventricular tachycardia, which converted to sinus rhythm after cardioversion. Cardiac computed tomography (CT) confirmed anomalous origin of the left main coronary artery from the non-facing sinus, with a slit-like ostium and acute take-off. Coronary artery ostioplasty using a CardioCel patch was performed. Postoperative recovery was excellent; mid-term surveillance with CT, magnetic resonance imaging, Holter monitoring, and stress echocardiography demonstrated a patent left main coronary artery, no evidence of ischemia, and normal cardiac function. This case highlights rapid resuscitation, early recognition, individualized surgical management, and mid-term follow-up in rare coronary artery anomalies. To our knowledge, this is the first reported use of a CardioCel patch in coronary ostioplasty for anomalous aortic origin of the coronary artery.

Mixed-pathogen infective endocarditis is uncommon and may be difficult to recognize when the clinical course is prolonged and nonspecific. We report a case of mixed Candida albicans and Brucella melitensis native aortic valve endocarditis in a 37-year-old previously healthy man who presented with five months of intermittent fever, chills, anorexia, fatigue, 7 kg weight loss, progressive dyspnea, and intermittent chest pain. Physical examination revealed fever, sinus tachycardia, wide pulse pressure, elevated jugular venous pressure, bibasilar crackles, and a loud early diastolic murmur. Laboratory testing was notable for leukocytosis, anemia, mild thrombocytosis, and elevated inflammatory markers. A transthoracic echocardiogram demonstrated severe aortic regurgitation with a large 19 mm aortic valve vegetation causing holodiastolic flow reversal in the descending thoracic aorta. A transesophageal echocardiogram revealed two large mobile vegetations causing severe leaflet malcoaptation with possible periannular extension. A cardiac CT scan revealed thickening of the aortic root consistent with abscess formation. Blood cultures were positive for Candida albicans and Brucella melitensis. Brucella serology was positive, with an agglutination titer of 1:640. The patient developed pulmonary edema requiring an urgent Bentall procedure with a mechanical composite graft. Valve tissue cultures were positive for Candida albicans, and histopathology from the resected valve was consistent with acute-phase infective endocarditis with features of necrosis, fibrin, and debris. The patient was placed on postoperative antifungal treatment with caspofungin followed by fluconazole suppression, and on Brucella-directed treatment with doxycycline, rifampin, and levofloxacin for a planned six-month course of therapy. A postoperative whole-body PET/CT scan using fluorine-18 fluorodeoxyglucose (18F-FDG) did not demonstrate any residual cardiac infection or extracardiac infectious foci. The patient was doing well clinically at the three-month follow-up, with no signs or symptoms of heart failure and no evidence of relapse or recurrence of fever. This is a rare case of destructive native aortic valve endocarditis with mixed fungal and zoonotic bacterial etiologies that required urgent surgical source control and prolonged combined antimicrobial therapy.

Recurrent glioblastoma (rGBM) is a leading brain malignancy with few therapeutic options. Here we present the complete results of a phase 1 trial investigating the safety and efficacy of autologous B7-H3-targeting chimeric antigen receptor T (CAR-T) cell (TX103) therapy for the treatment of rGBM. In this open-label, 3 + 3 dose-escalation trial, patients aged 18-75 years with B7-H3-positive (≥30%) rGBM received intracranial infusion of TX103 at three dose levels (DLs-2 × 10[7], 6 × 10[7] and 1.5 × 10[8] cells per infusion). Primary endpoints were safety, maximum tolerated dose (MTD), and recommended phase 2 dose (RP2D). Secondary endpoints included survival, pharmacokinetics and immunological response. Fifteen patients received a total of 72 intracranial infusions and 13 underwent repeated infusions. TX103 therapy was well tolerated, with no dose-limiting toxicities or MTD identified. Treatment-related adverse events (TRAEs) included low-grade cytokine release syndrome (86.7%), sinus tachycardia (53.3%), vomiting (53.3%), hypertension (53.3%) and elevated intracranial pressure (46.7%). Three grade 3 TRAEs considered serious adverse events occurred (elevated intracranial pressure, epilepsy and depressed consciousness), two at DL3. The 12-month overall survival (OS) rate was 66.7% and median OS was 19.1 months (95% confidence interval = 8.93, not reached) from first infusion. Disease control (stable disease or better) was achieved in 8 of 14 patients with measurable disease, including one complete response sustained through the latest follow-up. Cerebrospinal fluid showed a marked increase in CAR gene copy numbers and cytokine release, with minimal peripheral activity and no cumulative toxicity after repeated infusions. In conclusion, intracranial TX103 infusion demonstrated acceptable safety and encouraging efficacy in rGBM, supporting a future phase 2 evaluation at the RP2D (DL2, 6 × 10[7] cells per infusion). ClinicalTrials.gov registration: NCT05241392 .

This guided small group exercise is suitable for medical students who have completed basic lectures on electrocardiogram (EKG) interpretation. This activity was created for use within a third year required Emergency Medicine (EM) clerkship but can be implemented in other undergraduate medical education settings as well.

Sphingomonas paucimobilis is a rare opportunistic gram-negative bacillus increasingly reported in immunocompromised individuals. A 45-year-old male presented with right cervical swelling, fever, weight loss, anorexia, jaundice, and a discharging cervical sinus for two weeks. Examination revealed tachycardia, tachypnoea, pallor, icterus, cervical lymphadenopathy with sinus discharge, hepatosplenomegaly, and left-sided chest crepitations. Investigations showed neutrophilic leucocytosis, elevated C-reactive protein (CRP), deranged liver and renal function tests, and uncontrolled diabetes mellitus. Imaging demonstrated necrotic cervical lymphadenopathy, chronic calcific pancreatitis, and multiple bilateral pulmonary nodules with ground-glass opacities. Pus examination was negative for acid-fast bacilli, fungal elements, and a cartridge-based nucleic acid amplification test (CBNAAT) for tuberculosis; however, repeated cultures isolated Sphingomonas paucimobilis. Fine-needle aspiration cytology (FNAC) from a pulmonary nodule showed no malignancy and negative CBNAAT. The patient demonstrated marked clinical, laboratory, and radiological improvement with culture-guided piperacillin-tazobactam therapy and optimal glycaemic control. This case underscores the need to consider rare opportunistic infections as important differentials of disseminated tuberculosis.

COVID-19 is linked to diverse cardiovascular complications, including myocarditis, new-onset heart failure, and ventricular arrhythmias. Although premature ventricular contractions and bigeminy are recognized, the specific pattern of quadrigeminy remains rarely documented in this setting. A 57-year-old male with untreated hypertension presented with acute exertional chest pressure, dyspnea, and nocturnal wheezing over two weeks. On arrival, BP was 176/100 mmHg, HR was 101 bpm, and O2 saturation was 93% on room air. ECG showed sinus tachycardia with bigeminy and trigeminy, without QT or QTc prolongation. Lab results showed troponin 0.04 ng/mL, B-type natriuretic peptide (BNP) 241 pg/mL, and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) was positive. Chest CT revealed pulmonary edema, and echocardiogram showed a left ventricular ejection fraction (LVEF) of 40-45% with myocardial speckling. Telemetry showed runs of bigeminy, trigeminy, and quadrigeminy. He was diagnosed with acute hypoxic respiratory failure and COVID-19 myocarditis complicated by heart failure with mildly reduced ejection fraction (HFmrEF) and ventricular arrhythmias. Long-term follow-up is ongoing. This single-case report is based on comprehensive clinical, laboratory, electrocardiographic, telemetry, and imaging data from a community hospital admission. However, the limitations of this report are that this was a single case without cardiac MRI or biopsy confirmation. Hence, causality cannot be definitively established. To conclude, COVID-19 infection can cause myocarditis complicated by HFmrEF with rare arrhythmias, including quadrigeminy. Careful evaluation and individualized treatment are critical for optimal outcomes.