Daniel Robaei

Thromboembolic stroke with concurrent left atrial appendage and left atrial septal pouch thrombus.

A 71-year old man with permanent atrial fibrillation and recurrent thromboembolic strokes presented after sudden collapse followed by transient aphasia and quadriparesis, with evidence of recent cerebellar as well as right thalamic infarction on cranial computed tomography. He had been anticoagulated with warfarin for over 10 years, however at the time of presentation the INR was sub-therapeutic at 1.8. Transoesophageal echocardiography showed a dilated left atrium with severe spontaneous echocardiographic contrast, severely impaired left atrial appendage (LAA) contractile function (peak emptying velocity b10 cm/s), and a thrombus measuring 20×13mm at the tip of the LAA (Fig. 1). In addition, a 23×7 mm thrombus (Fig. 2; Supplemental video) was observed between the septumprimum and secundum, likely within a left atrial septal pouch. No extension of the thrombus into the right atriumwas observed. The remainder of the echocardiographic examination was normal. The patient made a full neurological recovery and was continued on anticoagulationwith a plan for strict INR control. The foramen ovale is a slit-like opening located in the inter-atrial wall of the fetal heart which enables right-to-left shunting during fetal development. This opening remains patent in 27% of the overall population [1]. Paradoxical thromboembolism from the venous to the arterial circulation through aprobe-patent foramenovale (PFO) is believed to contribute to the incidence of cryptogenic stroke, especially in young patients [2].

Everolimus-eluting Bioresorbable Vascular Scaffold Implantation in Real World and Complex Coronary Disease: Procedural and 30-day Outcomes at Two Australian Centres

BACKGROUND The Absorb BVS is a new generation of coronary stent designed to provide coronary arteries with mechanical support of a temporary nature, following balloon angioplasty. Clinical trials of the device have shown promising results thus far, however concern surrounds the deliverability of the device in real-world and complex coronary disease, and the possible higher incidence of early scaffold thrombosis when compared to conventional metallic drug-eluting stents. METHODS Implantation of the Absorb BVS was attempted in 152 lesions in 100 patients at two Sydney teaching hospitals, as part of a prospective registry. Lesions treated reflected a wide spectrum of real-world disease. Young patient age, long lesion length and involvement of the mid-portion of the left anterior descending artery were the strongest factors likely to influence the decision to use the Absorb BVS over conventional metallic stents. There were no restrictions on the lesion length, or on the number of lesions or vessels treated. Type C lesions made up 37% of all lesions treated with 64% of these being long lesions (>20mm). The Absorb BVS was successfully implanted in 98.8% of cases. Post-dilatation was performed in 95% of scaffolds. Peri-procedural non-ST elevation myocardial infarction occurred in four cases. Scaffold thrombosis did not occur in any patient at 30 days follow-up. There was no death, or need for target lesion revascularisation in-hospital or at 30 days. CONCLUSIONS High rates of procedural success were achieved with minimal complications with use of the Absorb BVS in real-world coronary disease, including complex disease. These results suggest that the reduced deliverability of the device can be largely overcome by meticulous lesion preparation, and that early scaffold thrombosis may be minimised through scaffold post-dilatation.

Ankyrin-B syndrome: a case of sinus node dysfunction, atrial fibrillation and prolonged QT in a young adult.

Ankyrin-B protein is involved in regulating expression and localisation of cardiac ion channels and transporters. Mutations of the ANK2 gene in the rare condition Ankyrin-B syndrome result in loss of function of the ankyrin-B protein which in turn leads to abnormal regulation of intracellular sodium and calcium and a predisposition to cardiac arrhythmia including torsades de pointes. We describe a rare case of this condition characterised by sinus node dysfunction, atrial fibrillation and prolonged QT syndrome in a young patient with a family history of sudden death. The management of Ankyrin-B syndrome may include avoidance of QT prolonging medications, insertion of a permanent pacemaker for sinus node dysfunction, or a cardioverter defibrillator for those at high-risk of sudden death from torsades de pointes.

Double Inter-atrial Septum: A Rare Cause of Cardioembolic Stroke

Double inter-atrial septum is an exceedingly rare congenital cardiac abnormality. We describe a case of transient ischaemic attack in a 53 year-old female found to have double inter-atrial septa on transthoracic and transoesophageal echocardiography. The midline inter-atrial chamber enclosed by the two septa was found to be continuous with the left atrium, with stasis in this accessory chamber predisposing to thrombus formation and cardio-embolic events. The case highlights the importance of transoesophageal echocardiography in the investigation of stroke, particularly in younger individuals.

Biventricular stress-induced (Tako-tsubo) cardiomyopathy complicated by right ventricular thrombus

Tako-tsubo cardiomyopathy is a syndrome characterised by transient ventricular dysfunction most commonly involving the left ventricle. Complications include congestive heart failure, hypotension and intracardiac thrombus formation predisposing to thromboembolic events. Right ventricular involvement may also occur but is usually less marked, with complications of right ventricular dysfunction not commonly seen.

Early graft failure complicating coronary artery bypass surgery for anomalous left coronary artery from the right coronary sinus

Anomalous left coronary artery from the right sinus is a recognized cause of myocardial ischemia, ventricular arrhythmia, and sudden cardiac death. The optimal management remains controversial with potential options including coronary artery bypass grafting with or without native vessel ligation, coronary artery re-implantation, and surgical un-roofing. In the case presented, bypass grafting of an anomalous left coronary artery was complicated by early graft failure due to competitive flow from the native vessel. <Learning objective: Coronary artery bypass grafting of coronary arteries with anomalous origin may be complicated by early graft failure resulting from competitive flow from the native vessel. The optimal management remains controversial but the surgical treatment chosen should be considered carefully.>.

Left main coronary artery origin from the right coronary sinus: rare, dangerous, and easy to miss on routine transoesophageal echocardiography.

[Extract] Coronary artery anomalies are rare and may occur as an isolated defect or in conjunction with other congenital cardiac malformations. Sudden cardiac death due to myocardial ischaemia is a sinister complication.

Pitfalls in Interpreting Bioprosthetic Aortic Valve Pressure Gradients: A Cautionary Tale!

High transvalvular pressure gradients following aortic valve replacement can be caused by several possible mechanisms. We present the case of an elderly woman with an elevated pressure gradient across an aortic valve bioprosthesis in the setting of complete heart block. After consideration of the presence of complete heart block, the hemodynamic profile of the specific prosthesis, and patient‐prosthesis mismatch, only a mild degree of stenosis was found to be attributable to degeneration of the prosthesis. There is no literature quantifying the hemodynamic effect of complete heart block on the pressure gradients across bioprosthetic aortic valves. In the case presented, the transvalvular peak and mean pressure gradients were reduced by 41% and 39%, respectively, following treatment of complete heart block by insertion of a permanent pacemaker.