Effects of continuous positive airway pressure therapy on left ventricular diastolic function: a randomised, sham-controlled clinical trial

Continuous positive airway pressure (CPAP) therapy may decrease left ventricular (LV) loads and improve myocardial oxygenation. In this study, we investigated the effect of CPAP on LV diastolic function compared with sham treatment in patients with severe obstructive sleep apnoea (OSA).

This 3-month prospective single-centre randomised sham-controlled trial analysed 52 patients with severe OSA. Patients were randomly assigned (1:1) to receive either CPAP or sham treatment for 3 months. The main investigator and patients were masked to the trial randomisation. The primary end-point was change of early diastolic mitral annular (e′) velocity over the 3-month period. Secondary end-points were pulse wave velocity (PWV), 24-h ambulatory blood pressure (BP) and variables of ventricular-vascular coupling at 3 months.

After 3 months of follow-up, CPAP treatment significantly increased the e′ velocity, and was greater than the sham treatment (0.65±1.70 versus −0.61±1.85 cm·s−1, p=0.014). The PWV, 24-h mean diastolic BP, night-time diastolic BP, arterial elastance index and ventricular-vascular coupling index after 3 months of follow-up decreased significantly in the CPAP group.

In patients with severe OSA, CPAP treatment for 3 months improved LV diastolic function more than sham treatment, and was accompanied by improvements in arterial stiffness and ventricular-vascular coupling.

D-dimer for prediction of long-term outcome in cryptogenic stroke patients with patent foramen ovale

Patent foramen ovale (PFO) is a potential cause of cryptogenic stroke, given the possibility of paradoxical embolism from venous to systemic circulation. D-dimer level is used to screen venous thrombosis. We investigated the risk of embolism and mortality according to the presence of PFO and D-dimer levels in cryptogenic stroke patients. A total of 570 first-ever cryptogenic stroke patients who underwent transesophageal echocardiography were included in this study. D-dimer was assessed using latex agglutination assay during admission. The association of long-term outcomes with the presence of PFO and D-dimer levels was investigated. PFO was detected in 241 patients (42.3 %). During a mean 34.0 ± 22.8 months of follow-up, all-cause death occurred in 58 (10.2 %) patients, ischaemic stroke in 33 (5.8 %), and pulmonary thromboembolism in 6 (1.1 %). Multivariate Cox regression analysis showed that a D-dimer level of > 1,000 ng/ml was an independent predictor for recurrent ischaemic stroke in patients with PFO (hazard ratio 5.341, 95 % confidence interval 1.648–17.309, p=0.005), but not in those without PFO. However, in patients without PFO, a D-dimer level of > 1,000 ng/ml was independently related with all-cause mortality. The risk of pulmonary thromboembolism tended to be high in patients with high D-dimer levels, regardless of PFO. Elevated D-dimer levels in cryptogenic stroke were predictive of the long-term outcome, which differed according to the presence of PFO. The coexistence of PFO and a high D-dimer level increased the risk of recurrent ischaemic stroke. The D-dimer test in cryptogenic stroke patients may be useful for predicting outcomes and deciding treatment strategy.

Different infarction patterns in patients with aortic atheroma compared to those with cardioembolism or large artery atherosclerosis

Aortic atheroma is a known cause of ischemic stroke. However, it is unclear whether ischemic stroke is caused by emboli from aortic atheroma or by accompanying atherosclerosis. In this study, we evaluated lesion patterns of patients with complex aortic plaque (CAP) to assume the underlying pathophysiology. Acute ischemic stroke patients who underwent transesophageal echocardiography were included. CAP was defined as a plaque in the proximal aorta ≥ 4 mm thick or with a mobile component. The diffusion-weighted imaging lesion patterns of patients with CAP were compared to those with large arterial atherosclerosis (LAA) or cardioembolism (CE). A total of 64 CAP patients, 127 LAA patients, and 80 CE patients were included. Small cortical pattern was more common in the CAP group (45.3%) than in the LAA (7.9%, p < 0.001) or the CE group (23.8%, p = 0.018). A large cortical pattern was more common in the CE group than in the CAP group (p < 0.001), whereas subcortical only pattern tended to be more common in the CAP group than in the CE group (p = 0.057). In multinominal analysis, the CAP group was more likely to have a small cortical lesion than the LAA group [odds ratio (OR) 14.63; 95% confidence interval (CI) 4.67-45.85] or the CE (OR 3.69, 95% CI 1.19-11.39) group. In conclusion, patients with CAP frequently had small cortical lesions or subcortical single lesion. These findings imply that ischemic stroke in aortic atheroma patients is associated with either small emboli or small artery disease.

Characteristics of Carotid Artery Structure and Mechanical Function and Their Relationships with Aortopathy in Patients with Bicuspid Aortic Valves

Patients with a bicuspid aortic valve (BAV) often have proximal aortic dilatation and systemic vascular dysfunction. We hypothesized that BAV patients would have different carotid artery structural and functional characteristics compared to tricuspid aortic valve (TAV) patients. In 28 patients with surgically confirmed BAV and 27 patients with TAV, intima media thickness (IMT), number of plaques, fractional area change (FAC), global circumferential strain (GCS), and standard deviation of CS (SD-CS) in both common carotid arteries were assessed using duplex ultrasound and velocity vector imaging (VVI). Patients with BAV were younger and had less co-morbidity, but showed a significantly larger ascending aorta (43.3 ± 7.5 vs. 37.0 ± 6.2 mm, p < 0.001) and a higher prevalence of aortopathy (61 vs. 30%, p = 0.021) than those with TAV. BAV patients showed a significantly lower IMT and fewer plaques. Although FAC and GCS were not significantly different between the two groups, they tended to be lower in the BAV group when each group was divided into three subgroups according to age. There was a significant age-dependent increase in IMT and decreases in FAC and GCS in the TAV group (p = 0.005, p = 0.001, p = 0.002, respectively), but this phenomenon was not evident in the BAV group (p = 0.074, p = 0.248, p = 0.394, respectively). BAV patients with aortopathy showed a higher SD-CS than those without aortopathy (p = 0.040), reflecting disordered mechanical function. In conclusion, BAV patients have different carotid artery structure and function compared with TAV patients, suggesting intrinsic vascular abnormalities that are less affected by established cardiovascular risk factors and more strongly related to the presence of aortopathy.

Assessment of myocardial viability based on dual-energy computed tomography in patients with chronic myocardial infarction: comparison with magnetic resonance imaging

PURPOSE

To evaluate the diagnostic performance of dual-energy computed tomography (DECT) for the assessment of myocardial viability compared with magnetic resonance imaging (MRI) in patients with chronic myocardial infarction (CMI).

METHODS AND MATERIAL

Twenty-six patients were prospectively enrolled, who underwent DECT and MRI at delayed phase. The infarct volumes for DECT and MRI were measured.

RESULTS

In per-segment and per-vessel analysis, DECT showed excellent diagnostic performance compared with MRI (diagnostic accuracy: 86.2%, 81.2% respectively). In volume analysis, DECT correlated well with MRI (r=0.966, p<0.0001).

CONCLUSIONS

DECT has excellent diagnostic performance for detecting CMI.

Clinical characteristics and mutation spectrum of GLA in Korean patients with Fabry disease by a nationwide survey: Underdiagnosis of late-onset phenotype

Fabry disease is a rare X-linked lysosomal storage disorder caused by an α-galactosidase A deficiency. The progressive accumulation of globotriaosylceramide (GL-3) results in life-threatening complications, including renal, cardiac, and cerebrovascular diseases. This study investigated the phenotypic and molecular spectra of GLA mutations in Korean patients with Fabry disease using a nationwide survey.This study included 94 patients from 46 independent pedigrees: 38 adult males, 46 symptomatic females, and 10 pediatric males. Each diagnosis was based on an enzyme assay and GLA gene mutation analysis.The mean age at presentation was 24 years (range, 5-65 years); however, the diagnoses were delayed by 21 ± 19 years after the onset of symptoms. Those patients with late-onset Fabry disease were diagnosed by family screening or milder symptoms at a later age. Forty different mutations were identified: 20 missense (50%), 10 nonsense (25%), 8 frameshift (20%), and 2 splice site (5%) mutations. Five of them were novel. IVS4+919G>A (c.936+919 G>A) was not detected among the 6505 alleles via newborn screening using dried blood spots. Enzyme replacement therapy (ERT) was performed in all the males and pediatric patients, whereas 75% of the symptomatic females underwent ERT for 4.2 ± 3.6 years.This study described the demographic data, wide clinical spectrum of phenotypes, and GLA mutation spectrum of Fabry disease in Korea. Most of the patients had classical Fabry disease, with a 4 times higher incidence than that of late-onset Fabry disease, indicating an underdiagnosis of mild, late-onset Fabry disease.

Prognostic significance of interventricular septal thickness in patients with AL amyloidosis

The major prognostic determinant of immunoglobulin light chain (AL) amyloidosis is cardiac involvement. However, the role of interventricular septal thickness (IVST), which reflects the extent of cardiac involvement, remains unclear. Therefore, we analyzed 77 patients with newly diagnosed AL amyloidosis and evaluated the prognostic role of IVST. Fifty patients (64.9%) had cardiac involvement and 17 patients (22.1%) showed IVST >15mm. Among all patients, the revised Mayo Clinic Stage III-IV and IVST >15mm were independently associated with inferior overall survival (OS) in a multivariable analysis. IVST >15mm was also adversely prognostic for OS in a subgroup of advanced-stage (revised Mayo Clinic stage III-IV) patients in a multivariable analysis (P<0.001). Furthermore, advanced-stage patients with IVST >15mm did not show survival benefit from treatment with bortezomib-based regimens and/or autologous stem-cell transplantation (ASCT). Our study demonstrated that IVST >15mm is adversely prognostic independent of the revised Mayo Clinic staging system in patients with AL amyloidosis. In addition, the degree of IVST might be used as a useful prognostic indicator that can guide the management of patients with AL amyloidosis especially at an advanced stage.

Percutaneous isolation of left atrial appendage thrombus

Most physicians regard left atrial appendage (LAA) thrombus as a contraindication for LAA occlusion due to risk of distal embolization which is a serious complication. Here we report a case of successfully implanted Amplazter cardiac plug without complication in elderly patients having LAA thrombus with recurrent embolic events despite oral anticoagulants for prevention of thromboembolic events. <Learning objective: LAA thrombus is not completely resolved in all cases and can be a potential source of stroke or embolization even during anti-coagulation. We would like to share a case that suffered from 6 strokes or embolizations despite anti-coagulation, warfarin or non-vitamin K antagonist oral anti-coagulants due to incomplete resolution of LAA thrombus. In this clinical situation, we can suggest LAA occlusion to isolate thrombus from LA and prevent further stroke or embolization.>.

Factors Determining Aortic Valve Dysfunction in Korean Subjects With a Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) disease has a male predominance of approximately 3:1 and shows diverse presentations about aortic valve dysfunction. This study aimed to find independent determinants for significant aortic stenosis (AS) or significant aortic regurgitation (AR) in adults with BAV. We retrospectively investigated the medical records of 1,073 subjects (773 men, mean age 55 ± 14 years) who were first diagnosed with BAV disease by transthoracic echocardiography. We excluded 52 subjects with both significant AS and significant AR. Of the remaining 1,021 subjects, 418 (41%) presented with significant AS, 249 (24%) showed significant AR, and the rest of the subjects were grouped into a normal functioning BAV (n = 354, 35%). BAV morphology was classified into the following 4 types according to position and pattern of raphe and cusps: (1) fusion of the right and left coronary cusps (type 1), (2) fusion of the right and noncoronary cusps (type 2), (3) fusion of the left and noncoronary (type 3), and (4) no raphe (type 0). Patients with significant AS were older, more likely to be women than men, and had a higher prevalence of type 0 BAV. Patients with significant AR were younger and were more likely to be men. In multivariate logistic regression analysis, women, older age, and type 0 or type 3 BAV were associated with significant AS. In contrast, men, hypertension, and chronic kidney disease were correlated with significant AR. Significant valve dysfunction in adults with first diagnosed BAV was closely associated with age, gender, and BAV morphology.

Deceleration time of left ventricular outflow tract flow as a simple surrogate marker for central haemodynamics at rest and as well as during exercise

Background

The shape and duration of left ventricular outflow tract (LVOT) flow has not been applied to assess the central haemodynamics, although LVOT flow is confronted with afterload of arterial system during systole. The aim of this study was to evaluate whether the LVOT flow parameters are related with central systolic blood pressure (BP) and arterial compliance at rest and as well as during exercise.

Methods

We studied 258 subjects (175 females, age 61 ± 11 years) with normal left ventricular (LV) systolic function who underwent supine bicycle stress echocardiography and arterial tonometry simultaneously at rest and at peak exercise. Deceleration time (DT) of LVOT flow and RR interval were measured and deceleration time corrected for heart rate (DTc) was calculated. Peripheral and central haemodynamic parameters including systolic and diastolic BP, and augmentation index at a heart rate of 75 (AIx@75) were assessed using radial artery tonometry. Carotid femoral pulse wave velocity (PWV) was measured.

ResultResults

Deceleration time corrected for heart rate was independently associated with central systolic BP and AIx@75 at rest (P < 0.001 and 0.006). Similarly, it also showed significant independent correlations with central systolic BP and AIx@75 during peak exercise (P = 0.006 and P = 0.021). In addition, DTc which measured both at rest and at peak exercise demonstrated significant positive correlations with PWV, suggesting association of prolonged DTc with arterial stiffening (P = 0.023 and P = 0.005).

Conclusion

Prolongation of LVOT flow DTc represents raised central systolic BP and increased arterial stiffness not only at rest but also during exercise. Therefore, central aortic pressures and arterial stiffness influence the DT of LVOT flow at rest as well as during exercise in individuals with normal LV systolic function.

Contrast-enhanced T1 mapping-based extracellular volume fraction independently predicts clinical outcome in patients with non-ischemic dilated cardiomyopathy: a prospective cohort study

OBJECTIVES

We aimed to evaluate the prognostic role of cardiac magnetic resonance imaging (CMR)-based extracellular volume fraction (ECV) in patients with non-ischemic dilated cardiomyopathy (NIDCM) and compare it with late gadolinium enhancement (LGE) parameters.

METHODS

This was a single-center, prospective, cohort study of 117 NIDCM patients (71 men, 51.9 ± 16.7 years) who underwent clinical 3.0-T CMR. Myocardial ECV and LGE were quantified on the left ventricular myocardium. The presence of midwall LGE was also detected. Nineteen healthy subjects served as controls. The primary end points were cardiovascular (CV) events defined by CV death, rehospitalization due to heart failure, and heart transplantation.

RESULTS

During the follow-up period (median duration, 11.2 months; 25^th-75^th percentile, 7.8-21.9 months), the primary end points occurred in 19 patients (16.2%). The ECV (per 3% and 1% increase) was associated with a hazard ratio of 1.80 and 1.22 (95% confidence interval [CI], 1.48-2.20 and 1.14-1.30, respectively; p < 0.001) for the CV events. Multivariable analysis also indicated that ECV was an independent prognostic factor and had a higher prognostic value (Harrell's c statistic, 0.88) than LGE quantification values (0.77) or midwall LGE (0.80).

CONCLUSION

CMR-based ECV independently predicts the clinical outcome in NIDCM patients.

KEY POINTS

• T1-mapping-based ECV is a useful parameter of risk stratification in NIDCM • ECV has a higher prognostic value than LGE • Contrast-enhanced T1-mapping CMR is a feasible and safe method.

Impact of Contrast Echocardiography on Assessment of Ventricular Function and Clinical Diagnosis in Routine Clinical Echocardiography: Korean Multicenter Study

Background

Fundamental echocardiography has some drawbacks in patients with difficult-to-image echocardiograms. The aim of this study is to evaluate impact of contrast echocardiography (CE) on ventricular function assessment and clinical diagnosis in routine clinical echocardiography.

Methods

Two hundred sixty patients were prospectively enrolled over 3 years in 12 medical centers in Korea. General image quality, the number of distinguishable segments, ability to assess regional wall motion, left ventricular (LV) apex and right ventricle (RV) visualization, LV ejection fraction, changes in diagnostic or treatment plan were documented after echocardiography with and without ultrasound contrast agent.

Results

Poor or uninterpretable general image was 31% before contrast use, and decreased to 2% (p<0.05) after contrast use. The average number of visualized LV segments was 9.53 before contrast use, and increased to 14.46 (p<0.001) after contrast use. The percentage of poor or not seen LV regional wall motion was decreased from 28.4% to 3.5% (p<0.001). The percentage of poor or not seen LV apex and RV was decreased from 49.4% to 2.4% (p<0.001), from 30.5% to 10.5% (p<0.001), respectively. Changes in diagnostic procedure and treatment plan after CE were 30% and 29.6%, respectively.

Conclusion

Compared to fundamental echocardiography, CE impacted LV function assessment and clinical decision making in Korean patients who undergo routine echocardiography.

Abstract TP178: Thrombi Occluding the Intracranial Artery Are Larger in Stroke Patients With Atrial Fibrillation in the Presence of Spontaneous Echo Contrast

Introduction: Spontaneous echo contrast (SEC) is frequently observed in patients with atrial fibrillation (AF). SEC represents red blood cell aggregates associated with increased thrombogenecity, which may produce larger thrombus formation. This can result in larger infarctions and severe stroke.

Hypothesis: Thrombus characteristics occluding the intracranial artery may differ between AF patients with concomitant SEC and those without.

Methods: This was a post hoc analysis of prospective cohort. Acute stroke patients with non-valvular AF who underwent transesophageal echocardiography and thin-section (1 or 1.25 mm) noncontrast CT between January 2008 and December 2014 were considered for this study. The volume and the density of thrombus were measured semi-automatically using three-dimensional image software, and compared between the patients with SEC and those without.

Results: Among 368 patients considered, thrombus was identified in 135 patients. Of the135 patients, 67 (49.6%) had SEC. The frequency of SEC was not different between patients with identified thrombi and those without (P=0.146). Thrombus volume was larger in the patients with SEC than those without (median [interquartile range], 75.0 mm 3 [46.1-142.9] versus 55.9 mm 3 [30.3-91.8]; P=0.013). As the degree of SEC increased, the thrombus volume increased (P=0.025). On multivariate analysis, the presence of SEC was independently associated with thrombus volume. (P=0.008) . Linear regression analysis showed positive association between initial National Institute of Health Stroke Scale scores and thrombus volume (P<0.001). However, thrombus density was not different between patients with SEC and those without (P=0.226).

Conclusions: This study suggests that increased thromogenecity by SEC in patients with AF might produce larger intracardiac thrombi and embolization, which resulted in larger thrombi occluding the intracranial artery and more severe stroke.