Intervention for arch obstruction after the Norwood procedure: Prevalence,associated factors,and practice variability

Objective

Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.

Risk modeling for ventricular assist device support in post-cardiotomy shock

BackgroundPost-cardiotomy shock (PCS) has a complex etiology. Although treatment with inotrops and intra-aortic balloon pump (IABP) support improves cardiac performance, end-organ injuries are common and lead to prolonged ICU stay, extended hospitalization and increased mortality. Early consideration of mechanical circulatory support may prevent such complications and improve outcome.MethodsBetween January 1997 and January 2002, 321 patients required IABP and inotropic support for PCS following coronary artery bypass grafting (CABG) at our institution. Perioperative variables including age, mixed venous saturation (MVO₂), inotropic requirements and LV function were analyzed using multivariate statistical methods. All explanatory variables with a univariate p value <0.10 were entered into a stepwise logistic regression model to predict hospital mortality. Odds ratios from significant variables (p < 0.05) in the regression model were used to compose a risk score.ResultsOverall hospital mortality was 16%. The independent risk factors for mortality in this population were: MVO₂ < 60% (OR = 3.2), milrinone > 0.5 μg/kg/min (OR = 3.2), age > 75 (OR = 2.7), adrenaline > 0.1 μg/kg/min (OR = 1.5). A 15-point risk score was developed based on the regression model. Hospital mortality in patients with a score >6 was 46% (n = 13/28), 3–6 was 31% (n = 9/29) and <3 was 11% (n = 29/264).ConclusionsA significant proportion of patients with PCS continue to face high mortality despite IABP and inotropic support. Advanced age, heavy inotropic dependency and poor oxygen delivery all predicted increased risk for death. Further investigation is needed to assess whether early institution of VAD support could improve outcome in this high-risk group of patients.     

Management of the single ventricle and potentially obstructive systemic ventricular outflow tract

Multi-stage palliation is the current management strategy for the treatment of children with various single ventricle (SV) cardiac malformations. The success of this strategy depends on the presence of favorable anatomic and hemodynamic criteria. Several SV anomalies have the potential of developing systemic ventricular outflow tract obstruction (SVOTO) that might be evident early on or progress later after palliative surgeries. SVOTO could result in ventricular hypertrophy, impaired diastolic function and subendocardial ischemia with subsequent deleterious effects on the SV and disturbance of some of those criteria for a successful multi-stage palliation strategy. Careful identification of SV patients at risk of developing SVOTO and proper planning of the optimal palliation sequence beginning at the 1st stage procedure are vital factors that would affect long-term outcomes in those patients. In the current review, we describe the morphology of SV patients with potential SVOTO risk, surgical procedures that address potential or present SVOTO, and optimal timing of those procedures within the multi-stage palliation chain. We attempt to provide a treatment algorithm for various patients taking into consideration their unique anatomic and physiologic characteristics.     

A Patient with Recent Chest Discomfort—Ischemia or No Ischemia? Postsystolic Shortening Comes to the Rescue

The diagnosis of myocardial ischemia in the emergency department can be challenging particularly in a patient in whom the chest discomfort has abated. Symptoms can be atypical, physical exam is often noncontributory, the electrocardiogram is usually nondiagnostic and cardiac enzymes remain normal. Thus, the decision for hospital admission or discharge can be quite difficult. Here, we describe such a patient in whom echocardiography with strain imaging identified the presence of postsystolic shortening (PSS) at the left ventricular apex. This suggested the likelihood of ischemic memory in the territory of the left anterior descending (LAD) artery. At coronary angiography a high grade stenosis was present in the proximal LAD artery. Our report highlights the role of echocardiography in the detection of myocardial ischemia and apical PSS as a marker of ischemic memory.