COVID-19 and ST elevations-keep an open mind: a case report.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has been associated with a range of cardiovascular manifestations, including myocardial injury and thrombo-embolism. Pulmonary embolism (PE) causing anteroseptal/anterior ST elevations that mimic myocardial infarction have previously been described. This phenomenon is thought to be related to right ventricular injury from large emboli. CASE SUMMARY: A 48-year-old woman with history of type 2 diabetes mellitus and hypertension presented to her local hospital with fever, cough, nausea, and dyspnoea. A test for SARS-CoV-2 was taken, and she was discharged with instructions to self-quarantine. She was subsequently notified of a positive SARS-CoV-2 result. Three days later, she re-presented with worsening dyspnoea and respiratory failure requiring intubation. On hospital Day 6, she became acutely hypoxic and hypotensive. Telemetry was noted to have ST changes, prompting ECG that revealed sinus tachycardia with prominent new ST elevations in her precordial leads. Transthoracic echocardiogram showed normal left ventricular function; however, the right ventricle was moderately dilated with positive McConnell's sign. Due to her unstable clinical state and high suspicion for PE, she was treated with tenecteplase 50 mg i.v. with complete resolution of her ST elevations and improved oxygenation. DISCUSSION: Given the high rates of thrombo-embolic events in COVID-19 patients, PE should be in the differential diagnosis of ST elevation, particularly in younger patients with few risk factors for coronary artery disease.

Use of the STEMI Team for Treatment of Patients With Pulmonary Embolism: A Pilot Study.

BACKGROUND: Patients with massive and submassive pulmonary embolism (PE) require rapid identification, triage, and consideration for reperfusion therapy. Use of an existing ST-segment elevation myocardial infarction (STEMI) team and activation protocol may be an effective means to care for these patients. OBJECTIVE: The objective of this analysis was to evaluate a pilot study using the STEMI team and a dedicated PE protocol for treatment of patients with massive and submassive PE. METHODS: From June 2014 to April 2016, a total of 40 patients with massive and submassive PE were evaluated. Baseline demographics, mode of hospital entry (transfer-in, in-hospital, and emergency department [ED] arrival), treatment time intervals (door to computed tomography PE protocol [CTPE], CTPE to invasive pulmonary angiogram, door to treatment time), procedures performed, and in-hospital clinical events were collected. RESULTS: Mean age was 56 ± 14 years, 17 (42%) were male, and 12 (30%) had a prior history of deep venous thrombosis or PE. Twenty-three patients (57%) had massive PE and 17 patients (43%) had submassive PE. Mode of hospital entry was transfer-in (38%), in-hospital (20%), and ED arrival (42%). Four patients (10%) presented with cardiac arrest, 8 patients (20%) required intubation, and 5 patients (12%) required extracorporeal membrane oxygenation. Ten patients (25%) received anticoagulation therapy or placement of inferior vena cava filter, 3 patients (7.5%) received diagnostic pulmonary angiography alone, and 27 patients (67.5%) received endovascular treatment. For patients arriving via the ED, door to CTPE was 4.9 ± 3.6 hours, CTPE to diagnostic pulmonary angiography was 7.8 ± 8.5 hours, and door to treatment time was 10.2 ± 9.0 hours. Endovascular devices utilized included combinations of rheolytic and other thrombectomy devices as well as catheter-directed fibrinolysis. Length of hospital stay was 15 ± 15 days and in-hospital survival rate was 90%. CONCLUSIONS: Use of an existing STEMI team and activation protocol is a feasible method to care for patients with massive and submassive PE. This pilot study demonstrated rapid treatment times with low in-hospital mortality.

Parallel generation of uniform fine droplets at hundreds of kilohertz in a flow-focusing module.

Droplet-based microfluidic systems enable a variety of biomedical applications from point-of-care diagnostics with third world implications, to targeted therapeutics alongside medical ultrasound, to molecular screening and genetic testing. Though these systems maintain the key advantage of precise control of the size and composition of the droplet as compared to conventional methods of production, the low rates at which droplets are produced limits translation beyond the laboratory setting. As well, previous attempts to scale up shear-based microfluidic systems focused on increasing the volumetric throughput and formed large droplets, negating many practical applications of emulsions such as site-specific therapeutics. We present the operation of a parallel module with eight flow-focusing orifices in the dripping regime of droplet formation for the generation of uniform fine droplets at rates in the hundreds of kilohertz. Elevating the capillary number to access dripping, generation of monodisperse droplets of liquid perfluoropentane in the parallel module exceeded 3.69 × 10(5) droplets per second, or 1.33 × 10(9) droplets per hour, at a mean diameter of 9.8 µm. Our microfluidic method offers a novel means to amass uniform fine droplets in practical amounts, for instance, to satisfy clinical needs, with the potential for modification to form massive amounts of more complex droplets.

Scaled-Up Production of Monodisperse, Dual Layer Microbubbles Using Multi-Array Microfluidic Module for Medical Imaging and Drug Delivery.

The production of uniform-sized and multilayer microbubbles enables promising medical applications that combine ultrasound contrast and targeted delivery of therapeutics, with improvements in the consistency of acoustic response and drug loading relative to non-uniform populations of microbubbles. Microfluidics has shown utility in the generation of such small multi-phase systems, however low production rates from individual devices limit the potential for clinical translation. We present scaled-up production of monodisperse dual-layered microbubbles in a novel multi-array microfluidic module containing four or eight hydrodynamic flow-focusing orifices. Production reached 1.34 × 10(5) Hz in the 8-channel configuration, and microbubble diameters in the high-speed regime (> 5 × 10(4) Hz) ranged between 18.6-22.3 µm with a mean pooled polydispersity index under 9 percent. Results demonstrate that microfluidic scale-up for high-output production of multilayer bubbles is possible while maintaining consistency in size production, suggesting that this method may be appropriate for future clinical applications.