Left atrial shape as a marker of atrial myopathy in embolic stroke of undetermined source.

AIMS: Embolic Stroke of Undetermined Source (ESUS) results in significant morbidity. A left atrial (LA) myopathy is implicated in a proportion of these patients. We hypothesized that LA shape varies by cause of stroke (cardioembolic versus ESUS). METHODS AND RESULTS: 236 ischemic stroke, atrial fibrillation (AF) patients and controls were recruited prospectively. AF was classified as paroxysmal (PAF) or persistent AF (PersAF). Stroke patients comprised cardioembolic stroke (CE) secondary to AF and ESUS. There were 81 AF (47 PAF, 34 PersAF), 50 ESUS, 57 CE patients (subdivided into CE with PAF (CEpaf) and CE with PersAF (CEpers) and 48 controls. Echocardiographic parameters including LA volume, function, and shape/sphericity (3D LA-sphericity and 2D-derived LA-circularity, ellipticity, sphericity and eccentricity indices) were evaluated. Increased LA volume and sphericity with LA dysfunction was present in CE, AF and ESUS groups compared to controls. K-means cluster analysis demonstrated a spectrum of LA myopathy with controls at the lowest and CEpers and PersAF at the upper extremes, with ESUS, PAF and CEpaf being similar and falling between these extremes. After adjusting for age, sex and left ventricular (LV) and LA parameters, LA sphericity markers differentiated ESUS from controls (p < 0.01). CONCLUSIONS: Alterations in LA shape are present in ESUS, AF and CE patients, particularly increased spherical remodelling. The novel markers of LA sphericity proposed may identify LA myopathy in ESUS patients and potentially guide management for secondary prevention.

Left atrial mechanics evaluated by two-dimensional strain analysis: alterations in essential hypertension.

BACKGROUND: Hypertension is a cardiovascular risk factor that predisposes to cardiac structural alterations namely increased left ventricular (LV) wall thickness, reduced LV compliance and diastolic dysfunction, with consequent left atrial (LA) dilation and functional impairment. In this article, we evaluated differences in left atrial structure and function using two-dimensional speckle tracking echocardiography in patients with hypertension compared with controls. METHODS: This was a retrospective cross-sectional study of 208 hypertensive patients and 157 controls who underwent a comprehensive transthoracic echocardiogram. Patients with hypertension were stratified by the presence of left ventricular hypertrophy (LVH). RESULTS: Non-LVH hypertension patients had lower left atrial reservoir strain (LAS RES ) (34.78 ±â€Š29.78 vs. 29.78 ±â€Š6.08; P  = 0.022) and conduit strain (LAS CD ) (19.66 ±â€Š7.29 vs. 14.23 ±â€Š4.59; P  = 0.014) vs. controls despite similar left atrial volumes (LAV) . Left atrial contractile strain (LAS CT ) was not significantly different between non-LVH hypertension patients and controls (15.12 ±â€Š3.77 vs. 15.56 ±â€Š3.79; P  = 0.601). Left atrial mechanical dispersion was significantly higher in the LVH group compared with the non-LVH hypertension group (42.26 ±â€Š13.01 vs. 50.06 ±â€Š14.95; P  = 0.009). In multivariate regression analysis, LVH correlated with left atrial mechanical dispersion ( P  = 0.016). An age-hypertension interaction independently correlated with LAS CT ( P  < 0.001). CONCLUSION: Hypertension results in functional left atrial changes even before development of LV hypertrophy and structural left atrial changes with increased left atrial volume. We demonstrate both a likely hypertension-associated left atrial myopathy that prevents age-related compensatory increase in left atrial contractile function, and impact of LVH in hypertension on left atrial dyssynchrony.

Longitudinal strain with speckle-tracking echocardiography predicts electroanatomic substrate for ventricular tachycardia in nonischemic cardiomyopathy patients.

Background: Longitudinal strain (LS) derived from speckle-tracking echocardiography (STE) corresponds to regions of scar in ischemic cardiomyopathy. Objective: We investigated if regional LS abnormalities correlate with scar location and scar burden, identified using high-density electroanatomic mapping (EAM) in nonischemic cardiomyopathy (NICM). Methods: Fifty NICM patients with ventricular tachycardia (VT) underwent echocardiography; multilayer (endocardial, midmyocardial, and epicardial) regional LS and global LS (GLS) were evaluated prior to EAM for detection of low-voltage scar. Patients were divided into 3 groups by EAM left ventricular scar location: (1) anteroseptal (group 1, n = 20); (2) inferolateral (group 2, n = 20); and (3) epicardial scar (group 3; n = 10). We correlated (1) location of scar to regional LS and (2) regional strain and GLS to scar percentage. Results: Regional LS abnormalities correlated with EAM scar in all groups. Segmental impaired LS and low voltage on EAM demonstrated concordance with scar in ∼75% or its border zone in 25% of segments. In groups 1 and 2, endocardial GLS showed a strong linear correlation with endocardial bipolar scar percentage (r = 0.79, 0.75 for groups 1 and 2, respectively; P < .001), whereas midmyocardial GLS correlated with unipolar scar percentage (r = 0.82, 0.78 for groups 1 and 2, respectively; P < .001). In group 3, epicardial regional LS and GLS correlated with epicardial bipolar scar percentage (r = 0.72, P < .001). Conclusion: Regional abnormalities on LS predict scar location on EAM mapping in patients with NICM. Moreover, global and regional LS correlate with scar percentage. STE could be used as a noninvasive tool for localizing and quantifying scar prior to EAM.

Electrocardiographic Characteristics and Their Correlation with Echocardiographic Alterations in Fabry Disease.

Fabry disease (FD) is an X-linked disorder with α-galactosidase A deficiency. Males (>30 years) and females (>40 years) often present with cardiac manifestations, predominantly left ventricular hypertrophy (LVH). The aim of this study was to evaluate electrocardiographic (ECG) characteristics within FD patients to identify gender related differences, and to additionally explore the association of ECG parameters with structural and functional alterations on transthoracic echocardiography (TTE). Retrospective cross-sectional analysis of 45 FD patients with contemporaneous ECG and TTE was performed and compared to age and gender matched healthy controls. FD patients demonstrated alterations in several ECG parameters particularly in males, including prolonged P-wave duration (91 vs. 81 ms, p = 0.022), prolonged QRS duration (96 vs. 84 ms, p < 0.001), increased R-wave amplitude in lead I (8.1 vs. 5.7 mV, p = 0.047), increased Sokolow-Lyon index (25 vs. 19 mV, p = 0.002) and were more likely to meet LVH criteria (31% vs. 7%, p = 0.006). FD patients with impaired basal longitudinal strain (LS) on TTE were more likely to meet LVH criteria (41% vs. 0%, p = 0.018). Those with more advanced FD (increased LV wall thickness on TTE) were more likely to meet LVH criteria but additionally demonstrated prolonged ventricular depolarization (QRS duration 101 vs. 88 ms, p = 0.044). Therefore, alterations on ECG demonstrating delayed atrial activation, delayed ventricular depolarization and evidence of LVH were more often seen in male FD patients. Impaired basal LS, a TTE marker of early cardiac involvement, correlated with ECG abnormalities. Increased LV wall thickness on TTE, a marker of more advanced FD, was associated with more severe ECG abnormalities.

Low Incidence of Ischemic Stroke Associated With Thrombus Aspiration in STEMI Patients Undergoing Primary PCI.

BACKGROUND: Thrombus aspiration (TA) during primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) was recommended to minimize distal embolization and to reduce thrombus burden prior to PPCI. Subsequent randomized trials showed no mortality benefit from TA and suggested an increased risk of stroke up to 180 days following TA, although it was not obvious that the procedure alone caused the strokes. METHODS AND RESULTS: This study retrospectively analyzed the periprocedural stroke rate in a series of STEMI patients treated with TA and PPCI at a single, large, tertiary hospital, where a rigorous uniform protocol of aspiration was used in all patients. Of 3734 patients, 1404 patients (38%; group 1) underwent TA as part of the PPCI procedure and 2330 patients (62%; group 2) did not undergo TA. There were no significant clinical differences between the 2 groups. In total, there were 20 strokes (0.54%), with 3 (0.2%) occurring in group 1, and 17 (0.7%) occurring in group 2 (P=.04). The majority of strokes occurred within 5 days of the procedure, and 3 (0.08%) were hemorrhagic. There were 22 intraprocedural deaths (0.6%), related to cardiogenic shock. There were no intraprocedural strokes. CONCLUSIONS: Very low stroke rates immediately post STEMI were seen in patients undergoing TA and PPCI in this real-world study. TA can be performed safely in STEMI patients undergoing PPCI with a short-term stroke risk equivalent to risk without TA. Further studies may be needed to explain the increased incidence of late stroke noted after TA and elucidate causative mechanisms.

Segmental Cardiac Radiation Dose Determines Magnitude of Regional Cardiac Dysfunction.

Background Subclinical left ventricular dysfunction detected by 2-dimensional global longitudinal strain post breast radiotherapy has been described in patients with breast cancer. We hypothesized that left ventricular dysfunction postradiotherapy may be site specific, based on differential segmental radiotherapy dose received. Methods and Results Transthoracic echocardiograms were performed at baseline, 6 weeks, and 12 months postradiotherapy on 61 chemotherapy-naïve women with left-sided breast cancer undergoing tangential breast radiotherapy. Radiation received within basal, mid, and apical regions for the 6 left ventricular walls was quantified from the radiotherapy treatment planning system. Anterior, anteroseptal, and anterolateral walls received the highest radiation doses, while inferolateral and inferior walls received the lowest. There was a progressive increase in the radiation dose received from basal to apical regions. At 6 weeks, the most significant percentage deterioration in strain was seen in the apical region, with greatest reductions in the anterior wall followed by the anteroseptal and anterolateral walls, with a similar pattern persisting at 12 months. There was a within-patient dose-response association between the segment-specific percentage deterioration in strain at 6 weeks and 12 months and the radiation dose received. Conclusions Radiotherapy for left-sided breast cancer causes differential segmental dysfunction, with myocardial segments that receive the highest radiation dose demonstrating greatest strain impairment. Percentage deterioration in strain observed 6 weeks postradiotherapy persisted at 12 months and demonstrated a dose-response relationship with radiotherapy dose received. Radiotherapy-induced subclinical cardiac dysfunction is of importance because it could be additive to chemotherapy-related cardiotoxicity in patients with breast cancer. Long-term outcomes in patients with asymptomatic strain reduction require further investigation.

Strain by speckle tracking echocardiography correlates with electroanatomic scar location and burden in ischaemic cardiomyopathy.

AIMS: Ventricular tachycardia (VT) in ischaemic cardiomyopathy (ICM) originates from scar, identified as low-voltage areas with invasive high-density electroanatomic mapping (EAM). Abnormal myocardial deformation on speckle tracking strain echocardiography can non-invasively identify scar. We examined if regional and global longitudinal strain (GLS) can localize and quantify low-voltage scar identified with high-density EAM. METHODS AND RESULTS: We recruited 60 patients, 40 ICM patients undergoing VT ablation and 20 patients undergoing ablation for other arrhythmias as controls. All patients underwent an echocardiogram prior to high-density left ventricular (LV) EAM. Endocardial bipolar and unipolar scar location and percentage were correlated with regional and multilayer GLS. Controls had normal GLS and normal bipolar and unipolar voltages. There was a strong correlation between endocardial and mid-myocardial longitudinal strain and endocardial bipolar scar percentage for all 17 LV segments (r = 0.76-0.87, P < 0.001) in ICM patients. Additionally, indices of myocardial contraction heterogeneity, myocardial dispersion (MD), and delta contraction duration (DCD) correlated with bipolar scar percentage. Endocardial and mid-myocardial GLS correlated with total LV bipolar scar percentage (r = 0.83; 0.82, P < 0.001 respectively), whereas epicardial GLS correlated with epicardial bipolar scar percentage (r = 0.78, P < 0.001). Endocardial GLS -9.3% or worse had 93% sensitivity and 82% specificity for predicting endocardial bipolar scar >46% of LV surface area. CONCLUSIONS: Multilayer strain analysis demonstrated good linear correlations with low-voltage scar by invasive EAM. Validation studies are needed to establish the utility of strain as a non-invasive tool for quantifying scar location and burden, thereby facilitating mapping and ablation of VT.

Changes in left atrial phasic strain and mechanical dispersion: Effects of age and gender.

PURPOSE: Left atrial (LA) function by two-dimensional (2D) strain is an emerging tool with increasing clinical utility. Age and gender are key modulators of strain parameters; however, the specific time course for LA structural and functional changes is not clearly defined. METHODS: A total of 147 healthy individuals (20-69 years) underwent transthoracic echocardiography; subjects were evaluated by age (decade) and gender. LA and left ventricular (LV) volumetric and strain measurements were performed. RESULTS: Left atrial reservoir (ƐR) and conduit strain (ƐCD) with negatively correlated with age (r =-.36; r = -.56; P < .001, respectively) being significantly lower by the 6th and 5th decades, respectively. Contractile strain (ƐCT) positively correlated with age (r = .36; P < .001), being significantly higher by the 6th decade. ƐR and ƐCD were higher in young females (20-34 years) compared to young males (P = .033 and P < .001, respectively). ƐCT was significantly higher in middle-aged adult males (35-50yrs; P = .010), though seen later in females (≥51 years; P = .005). Standard deviation of time to positive strain (SD-TPS) significantly higher by the 5th decade and correlated with age in both males (r = .44; P <.001) and females (r = .40; P = .001). CONCLUSION: We demonstrate that ƐR and ƐCD are lower with age, with differing rates between males and females. As a compensatory mechanism for decline in ƐCD, ƐCT is higher, more notably in males; comparatively, females display a more prominent decline in ƐR and ƐCD with age. Alteration in electromechanical properties occurred in both genders with SD-TPS becoming higher with age.

Inter-vendor comparison of left atrial strain using layer specific strain analysis.

Left atrial strain (LAS) on transthoracic echocardiogram (TTE) is increasingly recognised to have clinical utility in cardiovascular disease. Differences in LAS measurements between vendors remains a barrier for clinical use. We sought to compare LAS between two commonly used software platforms; the layer-specific endocardial and mid-myocardial measurements of LAS on General Electric (GE) Echopac were compared to TomTec strain. LAS was measured in 88 individuals with no previous cardiac history and 40 paroxysmal AF (PAF) patients, in sinus rhythm at TTE. Conventionally, LAS measured using GE Echopac is mid-myocardial strain (GE-mid); additionally, endocardial (GE-endo) LAS was evaluated. Both LAS measurements by GE were compared to TomTec-Arena (v2.30.02) measurements. Reservoir (ƐR), contractile (ƐCT) and conduit (ƐCD) phasic strain were evaluated. Both GE-mid and GE-endo LAS correlated well with TomTec LAS. On Bland-Altman analysis, GE-mid LAS measurements were systematically lower than TomTec LAS (ƐR: mean difference (MD) - 6.08%, limits of agreement (LOA) - 12%, 0%, ƐCT: MD - 0.8%, LOA - 7%, 5%, ƐCD: MD - 5.2% LOA - 12%, 1%). GE-endo LAS demonstrated no systematic difference from TomTec LAS, but had wider limits of agreement (ƐR: MD 0.41%, LOA - 7%, 8%, ƐCT: MD 0.50%, LOA - 6%, 7%, ƐCD: MD - 0.08%, LOA - 7%, 7%). ƐR had the best reproducibility. Mid-myocardial LAS, routinely evaluated by GE Echopac software, systematically underestimates LAS compared to TomTec. Using GE endocardial LAS eliminated this bias, but introduced greater variation between measurements. Serial measurements of LAS should therefore be performed on the same vendor system.

Differing mechanisms of atrial fibrillation in athletes and non-athletes: alterations in atrial structure and function.

AIMS: Atrial fibrillation (AF) is more common in athletes and may be associated with adverse left atrial (LA) remodelling. We compared LA structure and function in athletes and non-athletes with and without AF. METHODS AND RESULTS: Individuals (144) were recruited from four groups (each n = 36): (i) endurance athletes with paroxysmal AF, (ii) endurance athletes without AF, (iii) non-athletes with paroxysmal AF, and (iv) non-athletic healthy controls. Detailed echocardiograms were performed. Athletes had 35% larger LA volumes and 51% larger left ventricular (LV) volumes vs. non-athletes. Non-athletes with AF had increased LA size compared with controls. LA/LV volume ratios were similar in both athlete groups and non-athlete controls, but LA volumes were differentially increased in non-athletes with AF. Diastolic function was impaired in non-athletes with AF vs. non-athletes without, while athletes with and without AF had normal diastolic function. Compared with non-AF athletes, athletes with AF had increased LA minimum volumes (22.6 ± 5.6 vs. 19.2 ± 6.7 mL/m2, P = 0.033), with reduced LA emptying fraction (0.49 ± 0.06 vs. 0.55 ± 0.12, P = 0.02), and LA expansion index (1.0 ± 0.3 vs. 1.2 ± 0.5, P = 0.03). LA reservoir and contractile strain were decreased in athletes and similar to non-athletes with AF. CONCLUSION: Functional associations differed between athletes and non-athletes with AF, suggesting different pathophysiological mechanisms. Diastolic dysfunction and reduced strain defined non-athletes with AF. Athletes had low atrial strain and those with AF had enlarged LA volumes and reduced atrial emptying, but preserved LV diastolic parameters. Thus, AF in athletes may be triggered by an atrial myopathy from exercise-induced haemodynamic stretch consequent to increased cardiac output.

Right ventricular speckle tracking strain echocardiography in patients with acute pulmonary embolism.

Right atrial (RA) and right ventricular (RV) parameters assessed by traditional echocardiography lack sensitivity to identify pulmonary embolism (PE). We sought to determine if alterations in RV free wall longitudinal strain (FWS) would be present in PE patients and improve evaluation. This retrospective study comprised of 84 consecutive PE patients from 2 centres, with adequate transthoracic echocardiography (TTE) images for RV FWS analysis. PE patients were compared to 66 healthy controls. Compared to controls, PE patients had increased RV parasternal long-axis diameter (RVPLAX) (33.4 ± 5.8 mm vs 39.9 ± 4.1 mm) and RA area (17.4 ± 5.6 cm2 vs 14.5 ± 3.1 cm2) (p < 0.001 for both). RV function was reduced in PE patients (RV fractional area change 31.1 ± 13.2% vs 41.7 ± 9.1%, TAPSE 17.0 ± 4.5 vs 21.3 ± 2.2 mm; p < 0.001 for both). RV FWS was reduced in PE patients (-14.4 ± 7.2% vs - 26.0 ± 4.4%, p < 0.001). RV FWS was the best discriminator for PE (AUC 0.912). In comparative multiple logistic regression models for PE, the model which included traditional measures of RV size and function and RV FWS, produced a powerful classifier (AUC 0.966, SE 0.013) with significantly better performance (p < 0.022) than the model without RV FWS (AUC 0.921, SE 0.024). RV FWS is a discriminator of PE patients; addition of RV FWS to existing parameters of RV size and function, significantly improves sensitivity and specificity for diagnosis of PE, and may play a role in diagnosis and guiding therapy. Validation in other PE groups is required to confirm these observations and its prognostic value needs evaluation.

Focal Ventricular Tachycardias in Structural Heart Disease: Prevalence, Characteristics, and Clinical Outcomes After Catheter Ablation.

OBJECTIVES: This study sought to summarize the procedural characteristics and outcomes of patients with structural heart disease (SHD) who have focal ventricular tachycardia (VT). BACKGROUND: Scar-mediated re-entry is the predominant mechanism of VT in SHD. Some SHD patients may have a focal VT mechanism that remains poorly described. METHODS: An extended induction protocol incorporating programmed electrical stimulation, right ventricular burst pacing and isoprenaline was used to elucidate both re-entrant and focal VT mechanisms. RESULTS: Eighteen of 112 patients (16%) with SHD undergoing VT ablation over 2 years had a focal VT mechanism elucidated (mean age 66±13 years; ejection fraction 46±14%; nonischemic cardiomyopathy 10). Repetitive failure of termination with antitachycardia pacing (ATP) (69% of patients) or defibrillator shocks (56%) was a common feature of focal VTs. A median of 3 VTs per patient were inducible (28 focal VTs, 34 re-entrant VTs; 53% of patients had both focal and re-entrant VT mechanism). Focal VTs more commonly originated from the right ventricle (RV) than the left ventricle (LV) (67% vs. 33%, respectively). In the RV, the RV outflow tract was the most common site (33% of all focal VTs), followed by the RV moderator band (22%), apical septal RV (6%), and lateral tricuspid annulus (6%). The lateral LV (non-Purkinje) was the most common LV focal VT site (16%), followed by the papillary muscles (17%). After median follow-up of 289 days, 78% of patients remained arrhythmia-free; no patients had recurrence of focal VT at repeat procedure. In patients with recurrence, defibrillator therapies were significantly reduced from a median of 53 ATP episodes pre-ablation to 10 ATP episodes post-ablation. During follow-up, 2 patients (11%) underwent repeat VT ablation; none had recurrence of focal VT. CONCLUSIONS: Focal VTs are common in patients with SHD and often coexist with re-entrant forms of VT. High failure rate of defibrillator therapies was a common feature of focal VT mechanisms. Uncovering and abolishing focal VT may further improve outcomes of catheter ablation in SHD.

Echocardiographic Predictors of Long-Term Mortality in Patients Presenting With Acute Pulmonary Embolism.

Pulmonary embolism (PE) is associated with a high mortality; whether echocardiographic evaluation at presentation predicts long-term adverse outcomes is of importance. We sought to determine if a composite of routinely obtained echocardiographic parameters could determine long-term adverse events in PE patients. Right ventricular (RV) size and function and right atrial (RA) size were retrospectively evaluated in 233 consecutive PE patients with an inpatient echocardiogram, and compared with 70 healthy controls; mortality at 3 years was confirmed. PE patients had increased RV size (RV parasternal long-axis diameter [RVPLAX] and RV end-diastolic volume [p < 0.001 for both]) and RA area (p < 0.001). RV function was reduced in PE patients (RV fractional area change and RV ejection fraction [p <0.001 for both]). Peak tricuspid regurgitation (TR) velocity was higher in the PE group. At follow-up (3.0 ± 2.1 years), 61 patients died; multivariable analysis demonstrated RVPLAX diameter >37 mm (hazard ratio [HR] 2.3, 95% confidence interval [CI] 1.3 to 4.2; p = 0.005), RA area >20 cm2 (HR 2.0, 95% CI 1.1 to 3.5; p = 0.016), and TR velocity >2.9 ms-1 (HR 1.9, 95% CI 1.1 to 3.4; p = 0.021), were independent echocardiographic predictors of mortality. Patients with all 3 "risk markers" had ∼17-fold increased mortality compared with those with no "risk markers" (HR 16.9, 95% CI 6.1 to 47.2; p < 0.001). In conclusion, a composite of routinely collected echocardiographic parameters, namely an enlarged RA and RV (RVPLAX diameter), and TR velocity, were independent predictors of mortality in PE patients, with an exponential increase in mortality when all 3 parameters were significantly altered. Prospective validation is required to confirm these preliminary observations.

Echocardiographic Strain in Clinical Practice.

The accurate evaluation of left ventricular (LV) function has been central to monitoring of therapy, institution of specific therapeutic interventions and as a prognostic marker for risk stratification in a variety of cardiovascular conditions. However, LV ejection fraction, the most commonly used measure of LV systolic function, is a 'coarse' measure of global LV function, with several limitations. Strain analysis, a measure of myocardial deformation, has come to the forefront more recently as a more sensitive measure of myocardial function than LV ejection fraction. Its utility in detection of early subclinical LV dysfunction, defining regional variation in specific cardiomyopathies, utility to monitor improvement with therapy and as a prognostic marker in a variety of cardiac conditions has led to its increasing use in clinical practice. This review will briefly summarise specific methodological aspects, use in diagnosis and prognostic utility of strain analysis in various cardiovascular conditions.

Persistent reduction in global longitudinal strain in the longer term after radiation therapy in patients with breast cancer.

BACKGROUND: More than 80% of breast cancer patients receive radiotherapy (RT). However, RT can lead to cardiotoxicity, which usually develops insidiously over years, making diagnosis difficult. It is also unknown whether early identification of at-risk patients might improve long-term outcome. We have previously described subclinical alterations, detected by two-dimensional speckle tracking strain echocardiography, in left ventricular (LV) function immediately following RT in breast cancer. HYPOTHESIS: Subclinical myocardial alterations in LV function consequent to RT cardiotoxicity, observed early, persist at 12 months. METHODS: 40 chemotherapy naive women with left-sided breast cancer, treated with surgery and adjuvant breast RT, were prospectively recruited from two tertiary hospitals. Transthoracic echocardiography was performed at baseline (pre-RT), 6 weeks post-RT, and 12 months post-RT. RESULTS: An increase in LV end diastolic and end systolic volumes was seen from baseline, consistent with persistent LV remodelling; however, due to the increase in both systolic and diastolic volumes over time, no change in LV ejection fraction (EF) was observed. Global longitudinal strain (GLS) and S' velocity remained significantly lower at 12 months post-RT. GLS dropped by >10% in 16 patients and by >20% in 4 patients compared to baseline. CONCLUSIONS: Subclinical cardiac dysfunction using strain analysis, evident early, persists one year after RT, despite unchanged conventional indices such as LVEF. Persistent GLS reduction may be of particular importance in breast cancer patients receiving concomitant chemotherapy. Longer term prospective studies are required to determine if reductions in strain post-RT are associated with future adverse cardiovascular events.

Coronary artery vasospasm in a patient with Churg-Strauss syndrome.

Patients with Churg-Strauss syndrome often suffer from unusual cardiac manifestations and sudden cardiac death. This differs from patients with other autoimmune disorders, who typically present with premature ischaemic heart disease. We report the case of a 56-year-old man with recurrent coronary vasospasm, including an inferoposterior ST-elevation myocardial infarction, complicated by bradycardic arrest. There was only minor coronary artery disease on coronary angiography. An elevated eosinophil count was noted. His medical history included allergic rhinitis with polyposis, adult-onset asthma and biopsy-proven eosinophilic oesophagitis. Review of his sinus biopsies demonstrated blood vessels with marked accumulation of eosinophils in extravascular areas. The patient, therefore, met the American College of Rheumatology criteria for Churg-Strauss syndrome. The patient was commenced on immunosuppression, with the return of the eosinophil count to within normal limits, and remains free of cardiovascular events over 24 months.

Clinical evaluation of a new technique to monitor return electrode skin temperature during radiofrequency ablation.

PURPOSE: Return electrode burns occur occasionally in cardiac radiofrequency ablation and more frequently in tumor radiofrequency ablation. A return electrode incorporating a thermochromic liquid crystal (TLC) layer, which changes color with temperature, has been shown in sheep studies to accurately indicate underlying skin temperature. We aimed to validate the accuracy of TLC-coated return electrodes in indicating skin temperature in the clinical setting of cardiac radiofrequency ablation. METHODS AND RESULTS: The top layer of a standard return electrode was replaced with TLC. Fluoro-optic thermometer (FOT) probes were laid on the skin side of the return electrode, which was then placed on the left lateral mid-thigh of 18 patients (mean age = 61 ± 12 years, 12 men) undergoing cardiac radiofrequency ablation. Return electrode photographs were taken when FOT temperature exceeded 35 °C. TLC color changes, observed in 11 patients, were converted to temperature and compared with FOT temperature. TLC temperature correlated well with FOT temperature (Pearson's coefficient = 0.97 ± 0.03). Bland-Altman analysis showed good agreement (mean temperature difference = -0.04 ± 0.08 °C, upper limit of agreement = 0.11 ± 0.005 °C, lower limit of agreement = -0.19 ± 0.005 °C). The maximum FOT temperature recorded was 39.6 °C. There was no thermal injury at the return electrode site on any patients, when assessed immediately after and the day following the procedure. CONCLUSION: TLC-coated return electrodes accurately indicate underlying skin temperature in cardiac radiofrequency ablation and may help prevent burns. This technology might be essential in high energy radiofrequency ablation.