Assessment of a model for overall left ventricular three-dimensional motion from MRI data

In this paper we present a complete methodology to evaluate a model for overall three-dimensional (3D) motion of the human left ventricle (LV) from MRI data. The left ventricular motion is approximated by a linear model associated with an affine transformation to determine parameters for non-rigid motion of the LV. The proposed method has been applied to a normal patient and to a patient with cardiac disease. Results obtained show that the linear model provides a fairly good approximation of normal left ventricular motion, whereas serious cardiac disease produces abnormal motion, yielding altered model performances.     

First heart sound: A phono-echocardiographic correlation with mitral,tricuspid, and aortic valvular events

We evaluated the relationship of S₁ recorded by phonocardiography at the mitral area with motion of the mitral, tricuspid, and aortic valves, recorded by simultaneous echocardiography in 20 cardiac patients with a normal PR interval. The first major component of S₁ coincided with mitral valve closure in 20 of 20 patients (100%) and also with tricuspid valve closure in 14 of 20 patients (70%). The second major component of S₁ coincided with aortic valve opening in 20 of 20 patients and also with tricuspid valve closure in six of 20 patients (30%). We conclude that the first major component of S₁ coincides with mitral valve closure in all patients but may also coincide with tricuspid valve closure in many patients, and the second major component of S₁ coincides with aortic valve opening in all patients but may also coincide with tricuspid valve closure in some patients.     

The effect of successful angioplasty on variables of signal-averaged electrocardiogram and ventricular wall motion in patients with a first myocardial infarction

The correlation among three variables of late potentials (LPs) obtained by signal-averaged electrocardiography (SAECG) and improvement of ventricular wall motion estimated by echocardiography were studied in 66 patients with a first acute myocardial infarction (MI). Patients with bundle-branch block, intraventricular conduction delay, multi-vessel disease, previous MI, repeat percutaneous transluminal coronary angioplasty (PTCA), or evidence of reinfarction during a 6-month follow-up were excluded. A total of 66 patients was divided into two groups, with (Group 1: n = 27, age 56 ± 11) or without (Group 2: n = 39, age 61 ± 10) improvement of ventricular wall motion. Three variables of LPs and ventricular wall motion index (WMI) estimated and scored by echocardiography at admission (WMI 1) and at 6 months after MI (WMI 2) were compared in each group. In Group 1 (WMI 1 vs. WMI 2, p < 0.002), 20 of 27 patients underwent successful angioplasty; in Group 2 (WMI 1 vs. WMI 2, p = NS), 7 of 39 patients had successful emergency angioplasty. There were significant differences in three variables of LPs between the time of admission and at 6 months after MI in Group 1 but not in Group 2. Higher incidence of LPs and greater frequency of successful emergency PTCA were found in Group 1 compared with Group 2. These results suggest that because myocardial ischemia is reversed by successful angioplasty, ventricular wall motion is improved and the arrythmogenic substrate that generates LPs is stabilized electrically. Stunned or hibernating myocardium may be the arrhythmogenic substrate that generates LPs.     

The ischemic segment and left ventricular function during exercise angina

Improvement of the quality of transpulmonary left ventriculograms by exercise was demonstrated in 5 patients in a pre-study. In the main study transpulmonary left ventriculography was performed in 10 patients with coronary artery disease (CAD) at rest and during exercise, producing maximum angina pectoris (AP). Left ventricular pressure was recorded simultaneously. The extent of CAD, demonstrated in all patients by coronary angiography, was quantitated by a score. In the exercise ventriculograms, local wall motion was quantitated by 14 hemiaxes. During exercise AP, all patients developed wall motion abnormalities not present at rest. There was a significant linear correlation between coronary score and number of abmormally shortening hemiaxes (< 30% shortening) during exercise-AP (y = 0.16 × + 4.34; r = 0.933). The number of anormal hemiaxes correlated significantly (p < 0.05) with left ventricular enddiastolic pressure (LVEDP), dp/dt min, endsystolic volume index, enddiastolic volume index, ejection fraction, stroke work index, minute work, compliance SV/ Δ PD/ESV, and cardiac index. During exercise AP the extent of ischemic wall motion abnormalities is determined by localization and severity of coronary artery lesions. The extent of ischemic impairment of wall motion determines the severity of impairment of left ventricular pump function, filling pressure, and maximum speed of relaxation. Transpulmonary left ventriculography during exercise AP is a safe and relatively simple method to quantitate the extent of ischemic wall motion abnormalities. It could be useful in the selection of patients for coronary artery surgery and in the assessment of the results of this operation.     

Swallowing performance in patients with vocal fold motion impairment

Twenty-seven patients with vocal fold motion impairment underwent detailed pharyngoesophagel manometry with a strain gauge assembly linked to a computer recorder. Nine were known to have lesions of the central vagal trunk or nucleus, 9 had recurrent laryngeal nerve (RLN) palsy, and the remainder were idiopathic. The site of the lesion was a more important determinant of subjective swallowing performance than the position of the involved cord at laryngoscopy. Patients with cental lesions had lower tonic and contraction upper esophageal sphincter (UES) pressures than 25 age-matched controls, suggesting that high cervical branches of the lower cranial nerves are important in UES excitatory innervation. RLN palsy patients showed significantly increased pharyngeal contraction amplitude and reduced pharyngoesophageal wave durations. The results suggest that the dysphagia associated with vocal fold motion impairment is not simply due to the disruption of laryngeal deglutitive kinetics, but to independent effects on pharyngeal function.     

Decreased amplitude of left ventricular posterior wall motion with notch movement to determine the left posterior septal accessory pathway in Wolff-Parkinson-White syndrome

OBJECTIVE—To determine preoperatively, by analysing asynchronous left ventricular wall motion, whether to approach through the right ventricle or the left ventricle when carrying out catheter ablation of the accessory pathway in Wolff-Parkinson-White syndrome, especially in patients with the pathway located on the septum.
METHODS—73 patients with manifest Wolff-Parkinson-White syndrome who underwent successful catheter ablation were studied. Location of accessory pathway was classified as right ventricular side: right anterior paraseptum, right anterior, right lateral, right posterior, anterior septum, midseptum, right posterior septum; left ventricular side: left posterior septum, left posterior, left lateral, left anterior. Asynchronous systolic wall motion was analysed by cross sectional echocardiography.
RESULTS—Echocardiography showed that the amplitude of left ventricular posterior systolic wall motion was reduced when the pathway was located on the left ventricular side as opposed to the right ventricular side (mean (SD), 11.1 (1.7) v 12.9 (1.1) mm, p < 0.001), especially in patients with left posterior septal accessory pathway (9.7 (0.8) mm). There were no overlapping values between the left posterior septal accessory pathway and the right ventricular side accessory pathway. Posterior wall notch motion was observed in all patients with a left posterior septal accessory pathway (9/9), but not at all in patients with pathways located on the right ventricular side of the septum. In patients with a septal accessory pathway, an ECG algorithm provided poor information (relatively low sensitivity, specificity, and predictive value) for determining whether the subsite faced either the left (left posterior septum) or the right ventricle (anterior septum, midseptum, right posterior septum).
CONCLUSIONS—Decreased amplitude of left ventricular posterior wall motion with notch movement is an important finding for accessory pathways located on the left posterior septum. These findings provided clinically useful information for determining whether to approach catheter ablation from the right or the left ventricle.


     

Value of notching and slurring of the resting QRS complex in the detection of ischemic heart disease

The resting 12-lead ECG has long been known to be an insensitive marker of underlying ischemic heart disease (IHD). The purpose of this study was to determine if QRS complex notching and slurring is of significant value as a diagnostic discriminator in the detection of IHD. The data from 205 consecutive patients coming to cardiac catheterization for evaluation of probable IHD were initially analyzed. Eighty-three patients were excluded based upon ventricular hypertrophy, bundle-branch block, lack of data, and pacemaker rhythm. The balance, 122 patients (mean age 61.7 years), were evaluated for angiographic evidence of IHD, ECG findings of QRS notching or slurring, and abnormal Q waves. The data revealed a high prevalence of QRS notching or slurring; 62.2% in those patients with IHD, double the prevalence of significant Q waves (33.3%). The two markers had an approximately equal prevalence (QRS notching or slurring 61.7% vs. Q waves 53.2%) in patients with angiographic evidence of infarction; however, in patients with less than infarct criteria for IHD, the prevalence of QRS notching or slurring was 62.8%, while only 11.6% showed abnormal Q waves. Analysis indicated that QRS notching or slurring has a sensitivity of 62.2% and a specificity of 93.8% for the detection of IHD. The study demonstrates that QRS notching or slurring is a moderately sensitive and a very specific marker of ischemic heart disease in selected patients when using the resting ECG, and is of greatest value in those patients with lesser degrees of ischemic myocardial injury where the prevalence of Q waves is low.     

Commissural Alignment After Balloon-Expandable Transcatheter Aortic Valve Replacement Is Associated With Improved Hemodynamic Outcomes

BackgroundTranscatheter aortic valve replacement (TAVR) is generally performed without control over the alignment of the bioprosthesis to the native aortic valve (AV) commissures. Data on the impact of commissural misalignment (CMA) on the clinical and hemodynamic outcome after TAVR are scarce.ObjectivesThe aim of this study was to investigate the impact of commissural misalignment (CMA) on the clinical and hemodynamic outcome in patients with severe tricuspid aortic stenosis undergoing TAVR using the balloon-expandable (BE) SAPIEN 3 valve (Edwards LifeSciences).MethodsClinical data of consecutive patients who underwent BE TAVR at Cedars-Sinai Medical Center (Los Angeles, California, USA) enrolled in the RESOLVE (Assessment of TRanscathetER and Surgical Aortic BiOprosthetic Valve Thrombosis and Its TrEatment With Anticoagulation) registry were retrospectively analyzed to evaluate CMA, which was defined as a neocommissure position >30° compared with native commissures on computed tomography.ResultsA total of 324 patients (36.6% female, median Society of Thoracic Surgeons score of 3.9%) were included in the analysis. CMA was present in 171 individuals (52.8%). At 30 days, rates of aortic regurgitation greater than mild (5.6%) and a residual AV gradient ≥20 mm Hg (7.4%) were not different between CMA and non-CMA patients. Commissural orientation was independently associated with a relative AV mean gradient increase >50% from discharge to 30 days (per increase of 10° misalignment; OR: 1.3; 95% CI: 1.0-1.4; P = 0.01). The long-term composite outcome of death or stroke was not different between groups (log-rank P = 0.29).ConclusionsIn patients with severe tricuspid aortic stenosis who undergo SAPIEN 3 TAVR, the neocommissures align randomly. Our data demonstrate that commissural alignment may impact device performance and clinical outcomes in patients undergoing BE TAVR. (Assessment of TRanscathetEr and Surgical Aortic BiOprosthetic VaLVve Dysfunction with Multimodality Imaging and Its TrEatment with Anticoagulation [RESOLVE]; NCT02318342)     

Low-dose dobutamine stress test for the evaluation of cardiac function using ultrafast computed tomography

High dose-dobutamine (DOB) has been previously used as a pharmacological stress test to evaluate wall motion abnormalities. As a result, recent stress echocardiography with low-dose DOB has been reported to be valuable for investigating stunned myocardium after thrombolysis. However, echocardiography requires an operator's skill and experience to evaluate wall motion abnormalities which are subjectively determined by the observer. In contrast, ultrafast computed tomography (UFCT) does not necessarily require extreme technical skill and experience. To evaluate the feasibility of stress UFCT with low-dose DOB, we scanned 10 normal subjects along the short-axis by 8-slice-multicine mode. After scanning at rest for baseline, we scanned during the administration of 4 and 8 m?g/kg/min of DOB, respectively, for 5 min. Ejection fraction, contraction, and thickening were higher during 8 m?g/kg/min of DOB than during 4 m?g/kg/min of DOB and baseline, while the above values were higher during 4 m?g/kg/min of DOB than during baseline (p < 0.01). It was possible to detect changes of cardiac function and wall motion due to low-dose DOB by UFCT. We therefore conclude that UFCT is a reliable modality for evaluating cardiac function and wall motion for low-dose DOB stress test because of its excellent spatial and contrast resolution.