SARS-CoV-2: Current Tools to Fight COVID-19 ST-Elevation Myocardial Infarction

The capacity of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to wreak havoc on the inflammatory and coagulation pathways via the cytokine storm has led to over 6.3 million fatalities globally. Based on recent data, the mechanism predominately involves the formation of microvascular thrombosis when pertaining to cardiovascular disease. However, a subset of coronavirus disease-2019 (COVID-19)-positive patients present emergently with acute ST-elevation myocardial infarction (STEMI) are found to have severe epicardial thrombosis which is refractory to traditional coronary revascularization. We have noted mortality in these patients presenting to our facility to be as high as 90% and all angiographically confirmed to have thrombus which was refractory to traditional therapy. We present a case series of COVID-19-positive patients presenting with STEMI found to have epicardial thrombus who were treated with different traditional STEMI therapies but with fatal outcomes. Other possible techniques including mechanical thrombectomy, optimizing traditional and nontraditional anticoagulation therapy with the use of early hemodynamic support may prove more efficacious to destroy thrombus and potentially improve mortality.

Intra-Caval Balloon Pump

This clinical image vignette describes the inadvertent placement of a balloon pump in the vena cava during a "code blue" scenario, and the lessons to be learned from that experience. The hemodynamic benefits of intra-aortic balloon pump during experimental cardiac arrest include shorter circulation time and increases in end-tidal CO2 and coronary perfusion pressure. However, the hemodynamic effects of venous diastolic augmentation during experimental cardiogenic shock vary, being detrimental in cases of low preload, and possibly beneficial in a high preload state. When performed emergently at the bedside, inadvertent intra-caval placement of a balloon pump can occur due to elevated venous pressures, in the presence of severe tricuspid regurgitation, or through an arteriovenous fistula. A similar radiographic appearance can also be seen in the presence of a right-sided aortic arch. Clues to improper position include an abnormal pressure waveform and the absence of hemodynamic changes or blood pressure augmentation.

Pop the balloon: rapid switch from Intra-aortic balloon pump to alternate device

When a patient with an intra-aortic balloon pump needs different support, it is simple to use a stiff 0.018-inch interventional wire (360 cm) to exchange the balloon for a new sheath. This allows the team to start with a balloon and then switch if the support is not sufficient.

Evaluation of an intraventricular balloon pump for short-term support of patients with heart failure

The high cost of ventricular assist devices results in poor cost-effectiveness when used as a short-term bridging solution, thus a low-cost alternative is desirable. The present study aimed to develop an intraventricular balloon pump (IVBP) for short-term circulatory support, and to evaluate the effect of balloon actuation timing on the degree of cardiac support provided to a simulated in vitro severe heart failure (SHF) patient. A silicone IVBP was designed to avoid contact with internal left ventricular (LV) features (ie, papillary muscles, chordae, aortic, and mitral valves) based on LV computed tomography data of 10 SHF patients with dilated cardiomyopathy. The hemodynamic effects of varying balloon inflation and deflation timing parameters (inflation duty [D] and end-inflation point [σ]) were evaluated in a purpose-built systemic mock circulatory loop. Three IVBP actuation timing categories were defined: co-, transitional, and counterpulsation. Compared to the SHF baseline, co-pulsation increased aortic flow from 3.5 to 5.2 L/min, mean arterial pressure from 72.1 to 94.8 mmHg and ejection fraction from 14.4% to 21.5%, while mean left atrial pressure decreased from 14.6 to 10 mmHg. Transitional and counterpulsation resulted in a double ventricular pulse and extended the duration of increased ventricular pressure, potentially impeding diastolic filling and coronary perfusion. This in vitro study showed the IVBP could restore the hemodynamic balance of a simulated SHF patient with dilated cardiomyopathy to healthy levels.