Schaff, Hartzell V.

ObjectivesWe aimed to assess the utility of changes in systolic and diastolic function by isoproterenol challenge in predicting symptom resolution post‐myectomy in selected patients with hypertrophic cardiomyopathy (HCM) and labile obstruction.BackgroundIn a subset of symptomatic HCM patients without resting/provocable obstruction on noninvasive assessment, isoproterenol challenge during hemodynamic catheterization may elicit labile left ventricular outflow tract (LVOT) obstruction, and demonstrate the effect of obstruction on diastolic function. These changes may determine whether patients achieve complete symptom resolution post‐myectomy.MethodsBetween February 2003 and April 2009, 18 symptomatic HCM patients without LVOT obstruction on noninvasive testing underwent isoproterenol provocation and septal myectomy due to presence of provocable gradient and were followed for 4 (IQR 3–7) years.ResultsThirteen (72.2%) had complete symptom resolution, while 5 (27.8%) had improved, but persistent symptoms. Those with provoked gradient >100 mm Hg or increase in left atrial pressure (LAP) with isoproterenol had symptom resolution.ConclusionsSymptomatic HCM patients without LVOT gradient on noninvasive testing may demonstrate labile obstruction with isoproterenol. With isoproterenol, patients with high LVOT gradient or increase in LAP concomitant with an increase in gradient achieved complete symptom resolution post‐myectomy. Thus, improved diastolic filling as well as outflow gradient production in patients with HCM may predict symptom response to myectomy. © 2016 Wiley Periodicals, Inc.

We present a novel case of acute ischemic stroke in the postoperative setting of open septal myectomy. A 24-year-old woman developed acute left hemiparesis and rightward eye deviation the morning after surgery. She underwent emergent endovascular stoke therapy by mechanical embolectomy with successful retrieval of a fragment of myocardium that was obstructing the right middle cerebral artery. To our knowledge there has been no previous case described of a myocardial fragment causing a proximal intracranial artery occlusion with resulting ischemia and infarction.

Exposure of the basal and midventricular septum through the aortic root to relieve obstruction in hypertrophic cardiomyopathy can be challenging. Inadequate myectomy will lead to persistent symptoms and disability. Adequate exposure of the obstructive left ventricular septum is of paramount importance in primary and redo myectomy. In selected patients, either at primary myectomy or at redo myectomy, septal excision can be approached through a left ventricular transapical incision when transaortic exposure is inadequate.

Background— In asymptomatic patients with severe aortic stenosis, guidelines recommend left ventricular ejection fraction (LVEF) of <50% as the threshold for referral for aortic valve replacement. We investigated the importance of LVEF on long-term outcome after aortic valve replacement in symptomatic and asymptomatic patients with severe aortic stenosis. Methods and Results— We retrospectively identified 2017 patients with severe aortic stenosis (aortic valve area<1 cm 2 , mean gradient≥40 mm Hg, or indexed aortic valve area<0.6 cm 2 /m 2 ) who underwent surgical aortic valve replacement from January 1995 to June 2009. Patients were divided into 4 groups depending on preoperative LVEF (<50% in 300 [15%] patients, 50%–59% in 331 [17%], 60%–69% in 908 [45%], and ≥70% in 478 [24%]). During follow-up of 5.3±4.4 years, 1056 (52%) patients died. A decrease in mortality was observed with increasing LVEF, P <0.0001; 5-year mortality estimates (95% confidence interval) were 0.41 (0.35–0.47), LVEF<50%; 0.35 (0.29–0.41), LVEF 50% to 59%; 0.26 (0.23–0.29), LVEF 60% to 69%; and 0.22 (0.18–0.26), LVEF≥70%. Compared with patients with LVEF≥60%, patients with LVEF 50% to 59% had increased mortality (hazard ratio [HR], 1.58; P <0.001), with similar risk increase in both symptomatic (HR, 1.56; P <0.001) and asymptomatic patients (HR, 1.58; P =0.006). Correcting for risk factors, LV mass index, aortic valve area, and stroke volume index, LVEF was independently predictive of mortality (HR, 0.88 per 10%; P <0.001). When this analysis was repeated in the subset of 1333 patients without history of coronary artery disease, LVEF remained associated with mortality (HR, 0.90 per 10%; P =0.009). Conclusions— LVEF is a powerful predictor of outcome in patients with severe aortic stenosis undergoing aortic valve replacement, independent of the presence of valve-related symptoms.

Background— Most patients with repaired tetralogy of Fallot require pulmonary valve replacement (PVR), but the evaluation for and management of ventricular arrhythmia remain unclear. This study is aimed at clarifying the optimal approach to this potentially life-threatening issue at the time of PVR. Methods and Results— A retrospective analysis was performed on 205 patients with repaired tetralogy of Fallot undergoing PVR at our institution between 1988 and 2010. Median age was 32.9 (range, 25.6) years. Previous ventricular tachycardia occurred in 16 patients (8%) and 37 (16%) had left ventricular dysfunction, defined as left ventricular ejection fraction <50%. Surgical right ventricular outflow tract cryoablation was performed in 22 patients (10.7%). The primary outcome was a combined event including ventricular tachycardia, out-of-hospital cardiac arrest, appropriate implantable cardioverter defibrillator therapy, and sudden cardiac death. Freedom from the combined event at 5, 10, and 15 years was 95%, 90%, and 79%, respectively. In the first year after PVR, 2 events occurred. Conversely, in the 22 patients who underwent surgical cryoablation, a single event occurred 7 years after PVR. A history of ventricular tachycardia and left ventricular dysfunction was associated with higher risk for the combined event (hazard ratio, 4.7; P =0.004 and hazard ratio, 0.8; P =0.02, respectively). Conclusions— Patients with repaired tetralogy of Fallot undergoing PVR with history of ventricular tachycardia or left ventricular dysfunction appear to be associated with a higher risk of arrhythmic events after operation. Events in the first year after PVR are rare, and in select high-risk patients, surgical cryoablation does not seem to increase arrhythmic events and may be protective.

Objective: To compare the safety and effectiveness of video-assisted thoracic surgery (VATS) versus conventional median sternotomy (open) in the repair of secundum atrial septal defect (ASD) or patent foramen ovale (PFO). Design: Among 415 consecutive patients undergoing open or VATS ASD/PFO closure between 1993 and October 2012, 153 patients were compared using 2:1 frequency matching (n = 102 open vs 51 VATS). Matching variables include age, gender, body surface area, past medical history of neurologic events, and need of patch closure. Median age was 43 years (3-71 years), and 67% were female. Results: There were no early deaths in either group. There were no conversions to open sternotomy. Although mean cross-clamp time (14.5 ± 7.6 vs 26.3 ± 13.2 minutes, P < .001) and bypass time (31.7 ± 13.8 vs 60.9 ± 20.9 minutes, P < .001) were longer in the VATS group, patients who underwent VATS had shorter postoperative ventilation time (7.5 ± 6.4 vs 4.4 ± 2.8 hours, P = .03) with 62.7% extubated in the operating room, along with shorter intensive care unit stay (26.7 ± 10.8 vs 19.1 ± 9.9 hours, P < .001) and hospital stay (5.2 ± 1.9 vs 3.5 ± 0.9 days, P < .001). At early follow-up (mean 1.5 years, maximum 4.2 years), there was no difference in need for reintervention. Of the 27 patients who underwent VATS ASD/PFO closure for a neurologic event, none had a recurrence. Conclusion: The use of VATS provides a safe, equally effective alternative to conventional sternotomy for ASD/PFO closure, using a less invasive approach.