Two-dimensional (2D) ultrasound or echocardiography is one of the most widely used examinations for the diagnosis of cardiac diseases. However, it only supplies the geometric and structural information of the myocardium. In order to supply more detailed microstructure information of the myocardium, this paper proposes a registration method to map cardiac fiber orientations from three-dimensional (3D) magnetic resonance diffusion tensor imaging (MR-DTI) volume to the 2D ultrasound image. It utilizes a 2D/3D intensity based registration procedure including rigid, log-demons, and affine transformations to search the best similar slice from the template volume. After registration, the cardiac fiber orientations are mapped to the 2D ultrasound image via fiber relocations and reorientations. This method was validated by six images of rat hearts ex vivo. The evaluation results indicated that the final Dice similarity coefficient (DSC) achieved more than 90% after geometric registrations; and the inclination angle errors (IAE) between the mapped fiber orientations and the gold standards were less than 15 degree. This method may provide a practical tool for cardiologists to examine cardiac fiber orientations on ultrasound images and have the potential to supply additional information for diagnosis of cardiac diseases

Background Approximately 5% of patients with an acute coronary syndrome are discharged from the emergency room with an erroneous diagnosis of non-cardiac chest pain. Highly accurate non-invasive stress imaging is valuable for assessment of low-risk chest pain patients to prevent these errors. Adenosine stress cardiovascular magnetic resonance (AS-CMR) is an imaging modality with increasing application. The goal of this study was to evaluate the negative prognostic value of AS-CMR among low-risk acute chest pain patients. Methods We studied 103 patients, mean 56.7 ± 12.3 years of age, with chest pain and no electrocardiographic evidence of ischemia and negative cardiac biomarkers of necrosis, who were admitted to the Cardiac Decision Unit of our institution. All patients underwent AS-CMR. A negative AS-CMR was defined as absence of all the following: regional wall motion abnormalities at rest; perfusion defects during stress (adenosine) and rest; and myocardial scar on late gadolinium enhancement images. The patients were followed for a mean of 277 (range 161-462) days. The primary end point was defined as the combination of cardiac death, nonfatal acute myocardial infarction, re-hospitalization for chest pain, obstructive coronary artery disease (>50% coronary stenosis on invasive angiography) and coronary revascularization. Results In 14 patients (13.6%), AS-CMR was positive. The remaining 89 patients (86.4%), who had negative AS-CMR, were discharged. No patient with negative AS-CMR reached the primary end-point during follow-up. The negative predictive value of AS-CMR was 100%. Conclusion AS-CMR holds promise as a useful tool to rule out significant coronary artery disease in patients with low-risk chest pain. Patients with negative AS-CMR have an excellent short and mid-term prognosis.

BACKGROUND: Significant paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) confers a worse prognosis. Symptoms related to significant PVL may be difficult to differentiate from those related to other causes of heart failure. Cardiovascular magnetic resonance (CMR) directly quantifies valvular regurgitation, but has not been extensively studied in symptomatic post-TAVR patients. METHODS: CMR was compared to qualitative (QE) and semi-quantitative echocardiography (SQE) for classifying PVL and prognostic value at one year post-imaging in 23 symptomatic post-TAVR patients. The primary outcome was a composite of all-cause death, heart failure hospitalization, and intractable symptoms necessitating repeat invasive therapy; the secondary outcome was a composite of all-cause death and heart failure hospitalization. The difference in event-free survival according to greater than mild PVL versus mild or less PVL by QE, SQE, and CMR were evaluated by Kaplan-Meier survival analysis. RESULTS: Compared to QE, CMR reclassified PVL severity in 48% of patients, with most patients (31%) reclassified to at least one grade higher. Compared to SQE, CMR reclassified PVL severity in 57% of patients, all being reclassified to at least one grade lower; SQE overestimated PVL severity (mean grade 2.5 versus 1.7, p=0.001). The primary and secondary outcomes occurred in 48% and 35% of patients, respectively. Greater than mild PVL by CMR was associated with reduced event-free survival for the primary outcome (p<0.0001), however greater than mild PVL by QE and SQE were not (p=0.83 and p=0.068). Greater than mild PVL by CMR was associated with reduced event-free survival for the secondary outcome, as well (p=0.012). CONCLUSION: In symptomatic post-TAVR patients, CMR commonly reclassifies PVL grade compared with QE and SQE. CMR provides superior prognostic value compared to QE and SQE, as patients with greater than mild PVL by CMR (RF>20%) had a higher incidence of adverse events.

Importance: In low-flow, low-gradient aortic stenosis (LFLG AS), the severity of left ventricular dysfunction remains a key factor in the evaluation of aortic valve replacement. Objective: To evaluate the clinical outcomes and changes in left ventricular ejection fraction (LVEF) after transcatheter aortic valve replacement (TAVR) in patients with LFLG AS and severe left ventricular dysfunction. Design, Setting, and Participants: This multicenter registry is a substudy of the True or Pseudo-Severe Aortic Stenosis-TAVI registry that included patients with classic LFLG AS, defined as a mean transvalvular gradient less than 35 mm Hg, an effective orifice area less than 1.0 cm 2 , and an LVEF of 40% or less. Patients were divided in groups with very low (<30%) LVEF and low (30%-40%) LVEF. Dobutamine stress echocardiography (DSE) was performed before TAVR in a subset with very low LVEF, and presence of contractile reserve was defined as an increase of 20% or more in stroke volume. Clinical outcomes were assessed at 1 and 12 months and yearly thereafter, and echocardiography was performed at 1-year follow-up. Retrospective data were collected from 2007 to 2013 and prospective data from January 2013 to March 2018. Data were analyzed from March to October 2018. Exposures: Transcatheter aortic valve replacement in patients with LFLG AS. Main Outcomes and Measures: Changes in LVEF over time; periprocedural and late mortality. Results: A total of 293 patients were included, including 128 (43.7%) with very low LVEF and 165 with low LVEF (56.3%). Their mean (SD) age was 80 (7) years, and most (214 [73.0%]) were men. The mean (SD) LVEF in the very low LVEF group was 22% (5%), compared with 37% (7%) in the low LVEF group (P <.001). There were no differences between groups in rates of periprocedural mortality and late mortality (median [interquartile range], 23 [6-38] months). Patients with very low LVEF displayed a greater increase in LVEF at the 1-year follow-up examination (mean absolute increase, 11.9% [95% CI, 8.8%-15.1%]), than the low LVEF group (3.6% [95% CI, 1.1%-6.1%]; P <.001). In 92 patients with very low LVEF who had preprocedural DSE, results showed a lack of contractile reserve in 45 (49%), but this had no effect on clinical outcomes or changes in LVEF over time. Conclusions and Relevance: In patients with LFLG AS and severe left ventricular dysfunction, TAVR was associated with similar clinical outcomes as in counterparts with milder left ventricular dysfunction. The TAVR procedure was associated with a significant increase in LVEF, irrespective of contractile reserve. These results support TAVR for LFLG AS, irrespective of the severity of left ventricular dysfunction and DSE results.

Transcatheter mitral valve replacement (TMVR) procedures can be an alternative to surgical valve replacement for high surgical risk patients with bioprosthetic mitral valves, annuloplasty rings, or severe mitral annular calcification (MAC). TMVR can trigger acute left ventricular outflow tract (LVOT) obstruction from permanent displacement of the native anterior mitral leaflet toward the left ventricular septum, more often among patients undergoing valve-in-ring and valve-in-MAC procedures. Although acute LVOT obstruction is well described in the literature, there are important additional complications of TMVR related to the length and/or redundancy of the anterior mitral valve that have been recognized after mitral valve surgery and have not been previously reported in the setting of TMVR. These additional complications include acute mitral regurgitation secondary to prolapsing native leaflet through the TMVR, frozen TMVR leaflet secondary to overhanging native leaflet and late LVOT obstruction in the neo-LVOT secondary to long native leaflet. Preprocedural planning with imaging (echocardiography and computed tomography) and measurement of anterior mitral leaflet length is critical important in understanding the risk for these complications. As transcatheter mitral valve technology proliferates, interactions with the anterior mitral leaflet after TMVR may be more frequent than initially anticipated. We believe that there is no advantage to an intact anterior leaflet and advocate removal or reduction of the leaflet prior to TMVR. © 2017 Wiley Periodicals, Inc.

Objectives: This study sought to use a new catheter technique to split the anterior mitral valve leaflet (AML) and prevent iatrogenic left ventricular outflow tract (LVOT) obstruction immediately before transcatheter mitral valve replacement (TMVR). Background: LVOT obstruction is a life-threatening complication of TMVR, caused by septal displacement of the AML. Methods: The procedure was used in patients with severe mitral valve disease and prohibitive surgical risk. Patients either had prior surgical mitral valve ring (n = 3) or band annuloplasty (n = 1) or mitral annular calcification with stenosis (n = 1). Iatrogenic LVOT obstruction or transcatheter heart valve dysfunction was predicted in all based on echocardiography and computed tomography. Transfemoral coronary guiding catheters directed an electrified guidewire across the center and base of the AML toward a snare in the left atrium. The externalized guidewire loop was then electrified to lacerate the AML along the centerline from base to tip, sparing chordae, immediately before transseptal TMVR. Results: Five patients with prohibitive risk of LVOT obstruction or transcatheter heart valve dysfunction from TMVR successfully underwent LAMPOON, with longitudinal splitting of the A2 scallop of the AML, before valve implantation. Multiplane computed tomography modeling predicted hemodynamic collapse from TMVR assuming an intact AML. However, critical LVOT gradients were not seen following LAMPOON and TMVR. Doppler blood flow was seen across transcatheter heart valve struts that encroached the LVOT, because the AML was split. Transcatheter heart valve function was unimpeded. Conclusions: This novel catheter technique, which resembles surgical chord-sparing AML resection, may enable TMVR in patients with prohibitive risk of LVOT obstruction or transcatheter heart valve dysfunction.

Dehiscence of a prosthetic heart valve or excessive rocking during the cardiac cycle is thought to preclude percutaneous paravalvular leak closure. However, surgical repair of paravalvular leak is associated with recurrent dehiscence and poor outcomes. We present the case of a symptomatic 74-year-old man in whom we performed percutaneous anchoring, involving multiple plugs and multimodal imaging, to stabilize a rocking mitral valve and close a substantial paravalvular leak caused by dehiscence. To our knowledge, using this technique to correct both conditions is novel.