ABSTRACT
Background: Treatment of symptomatic mitral valve stenosis in severe mitral annular calcification is a surgical challenge. Transcatheter options include transfemoral transcatheter mitral valve replacement (TMVR), which poses its own risks, the most significant is left ventricular outflow tract (LVOT) obstruction. Transatrial hybrid TMVR optimizes advantages of both traditional open-heart surgery and transcatheter valve replacement. Methods: Retrospective review of seven high-risk patients (deemed ineligible for traditional surgery) undergoing transatrial implantation of a SAPIEN 3 valve (Edwards Lifesciences, Irvine, CA) in the mitral position for severe symptomatic mitral stenosis. Laceration of the Anterior Mitral leaflets to Prevent Outflow ObstructioN procedure was not considered due to heavy leaflet calcifications. Results: Seven patients treated consecutively from June 2020 to July 2021 were included in this analysis. Mean age was 77 years;six were females, one was male. Average STS score was 9.8. Three patients had New York Heart Association (NYHA) class IV heart failure. Mean left ventricular ejection fraction was 62%. Dominant mitral valve pathology included mitral stenosis in all patients. Mean mitral valve gradient was 12 mmHg. All patients had circumferential annular calcification except one, who had predominantly anterior calcification. All patients received the Edwards SAPIEN 3 valve and had anterior leaflet resection. Surgical approach was at the discretion of the attending cardiac surgeon. Mean cardiopulmonary bypass time was 85 minutes;mean cross-clamp time was 36 minutes. No anchoring felt was used. Technical success was 100%, with no device embolization. There was no clinically significant LVOT obstruction. There were two deaths: one occurred during index hospitalization due to worsening heart failure secondary to torrential tricuspid regurgitation, and the second was 2 months later due to COVID-19 infection. Conclusion: Surgical hybrid transatrial TMVR for patients at high surgical risk is technically feasible with high procedure success. A relatively shorter cardiac ischemic duration, direct visualization and resection of the anterior mitral leaflet can allow for safe TMVR without risk of LVOT obstruction.
ABSTRACT
With the spread of the novel coronavirus disease 2019 (COVID-19) pandemic, an alarming number of patients now present with acute respiratory distress syndrome (ARDS). Conservative fluid management with diuresis in the ARDS patients improves lung function and decreases ventilator-dependent days. Several cardiac manifestations have been reported in COVID-19 patients including rhythm disorders, myocarditis, Takotsubo cardiomyopathy and myocardial infarction. A 65-year-old Asian female with a history of hypertension presented to the emergency department with cough, worsening dyspnea and palpitations of one-week duration. Investigations at admission were significant for a positive COVID-19 polymerase chain reaction test with an electrocardiogram (EKG) (Figure 1 Panel-A) revealing inferior ST-elevations. Troponin-T was elevated to 1162 ng/L with bedside echocardiogram revealing inferior hypokinesis. Due to concerns for acute ST-elevation myocardial infarction (STEMI), the patient underwent cardiac catheterization with no obvious coronary artery occlusion. A ventriculogram revealed apical ballooning and the patient was treated for COVID-19 induced Takotsubo cardiomyopathy. The patient developed worsening respiratory distress on hospitalization day 3 requiring oxygen supplementation with a high-flow nasal cannula. Conservative fluid regimen and diuretic therapy were being administered when the patient developed ventricular fibrillation and suffered a cardiac arrest. After successful resuscitation, a repeat EKG (Figure 1 Panel-B) demonstrated new anterior and inferior ST-elevations. The patient required increasing vasopressor support, and a repeat cardiac catheterization to rule out coronary artery thromboembolism induced STEMI was negative. A right heart catheterization revealed elevated SVR with decreased cardiac index. The patient clinically deteriorated despite negative fluid balance with recurrent malignant arrhythmias. A bedside echocardiogram performed revealed persistent apical hypokinesis and systolic anterior motion of anterior mitral leaflet (Figure 1 Panel-C) with flow acceleration at left ventricular outflow tract (LVOT) (Figure 1 Panel-D). Due to concerns of cardiogenic shock secondary to Takotsubo cardiomyopathy with dynamic LVOT obstruction physiology, the patient was treated with liberal intravenous fluid resuscitation and successfully weaned from vasopressor therapy. Although she was successfully extubated 2 days later, the patient, unfortunately, passed away later from a thromboembolic stroke. Severe COVID-19 infections are associated with catecholamine surge which may precipitate Takotsubo cardiomyopathy in the susceptible patient population. Female patients with Takotsubo cardiomyopathy are at increased risk of developing dynamic LVOT obstruction. In these patients, management of shock and ARDS can be challenging as the use of inotropic agents may result in hemodynamic instability. Our patient was successfully hemodynamically stabilized using fluid resuscitation once the inotropic support was withdrawn after identifying dynamic LVOT obstruction.
ABSTRACT
Background: A 35-year-old G1P1 woman with a history of bioprosthetic mitral valve (MVR) and aortic valve (AVR) replacements and a tricuspid valve annuloplasty for presumed rheumatic heart disease who presented at 35 weeks gestational age with COVID-19 ARDS and shock. Case: The patient arrived with ARDS requiring intubation and distributive shock. Transthoracic echocardiogram (TTE) revealed a small left ventricular (LV) cavity with LV hypertrophy, MVR with mean gradient of 14 mmHg, and a mid-peaking transaortic gradient of 96 mmHg consistent with fixed obstruction. This gradient was likely due to LV outflow tract obstruction (LVOTO) from the combination of a small LV cavity and septal angulation of the MVR struts rather than AVR dysfunction. The patient underwent emergent cesarean section. Decision-making: The maternal and fetal risks of ARDS and distributive shock were primary considerations in undergoing cesarean section. Decisions regarding management thereafter were driven by three elements of her clinical presentation - anticipated peripartum hemodynamic shifts, multivalvular disease, and ARDS. The increased plasma volume from postpartum autotransfusion risked worsening her ARDS but also potentially benefited the LVOTO through increased preload. The effect of lower postpartum cardiac output and heart rate on valvular obstruction in series also had to be considered. To balance these hemodynamic demands, after delivery, her vasopressors were switched from norepinephrine to phenylephrine, and she was judiciously diuresed. A postpartum TTE demonstrated improved transmitral gradients (mean 5 mmHg) but ongoing LVOTO. Higher filling pressures than otherwise ideal in ARDS were tolerated given persistent gradients. She was liberated from hemodynamic and ventilator support and transferred out of ICU care. Though she died of infectious complications weeks later, close collaboration between the critical care, obstetrical, and cardiovascular teams were essential to her care. Conclusion: Care of the peripartum patient with cardiovascular disease, especially valvular disease, must take into consideration both their cardiac pathology and expected peripartum hemodynamic shifts.
ABSTRACT
Background: In the setting of septic shock, an increase in sympathetic tone results in increased heart rate and contractility as well as decreased left ventricular (LV) end diastolic volume;these compensatory mechanisms can result in LV obstruction. Separately, following an MI, varying degrees of hypokinesis may result from infarcted myocardium. Case: A 75-year-old woman with COVID-19, acute respiratory distress syndrome, and septic shock was found to have a dynamic LV mid-cavitary obstruction on transthoracic echocardiogram (TTE). Three days later, the patient suffered a proximal left anterior descending STEMI and underwent percutaneous coronary intervention with drug-eluting stents. Follow-up TTE revealed mid-anterior and apical hypokinesis, with compensatory basal hyperkinesis and new systolic anterior motion of the mitral valve, resulting in an LV outflow tract (LVOT) obstruction, further exacerbated by underlying basal septal hypertrophy. A dynamic shift of the level of LV obstruction, from mid-cavitary to the outflow tract, was identified. Decision-making: Hemodynamic optimization in the setting of LVOT obstruction complicated by ischemic cardiomyopathy and distributive shock focused on supporting preload and afterload, while avoiding inotropic therapy. Conclusion: Prior case reports have demonstrated dynamic LV obstruction as a compensatory response to septic shock or as a sequelae of MI. However, this case highlights a rare presentation of shifting levels of obstruction. [Formula presented]