Does acute-phase beta blockade reduce left atrial appendage function in patients with chronic nonvalvular atrial fibrillation?

To investigate whether acute-phase beta-blocker therapy has a harmful effect on left atrial appendage (LAA) function in patients with chronic nonvalvular atrial fibrillation by transesophageal echocardiography (TEE), we evaluated 21 patients with normal left ventricular systolic function and a poorly controlled ventricular rate, despite the use of digoxin. Baseline parameters that were obtained included heart rate, blood pressure, LAA emptying velocities, and left atrial spontaneous echo contrast intensity. Then, each patient was given a bolus dose of 5 mg metoprolol. Ten minutes later, a second set of assessments was performed. After the first TEE studies, each patient began treatment with metoprolol (50 mg orally twice daily for 1 week). A second TEE study was performed after 1 week of continuous oral metoprolol therapy at maintenance dose, and values were again determined. The average resting apical heart rate was 91 +/- 7 bpm. As expected, beta-blocker therapy showed a marked decrease in heart rate at 10 minutes (79 +/- 6 bpm, P <.001) and at 1 week (71 +/- 4 bpm, P <.001). Beta-blocker therapy caused a significant reduction in systolic and diastolic blood pressures (144 +/- 16 / 93 +/- 6 mm Hg at baseline, 137 +/- 16 / 87 +/- 9 mm Hg at 10 minutes, and 135 +/- 12 / 86 +/- 8 mm Hg at 1 week, P <.001). With the beta-blocker therapy, the baseline transesophageal Doppler parameter of LAA emptying velocities (at baseline 24 +/- 7 cm/s) fell significantly at 10 minutes (19 +/- 7 cm/s, P <.001) and at 1 week (17 +/- 6 cm/s, P <.001) after initiation of beta-blocker therapy. After a bolus of metoprolol, spontaneous echo contrast intensity did not change in any patients, but 1 week later, it increased in 1 patient. In 2 patients who had not been found to have an LAA thrombus at baseline TEE study, the second TEE examination demonstrated new thrombi in the LAA. In conclusion, our findings suggest that in patients with chronic nonvalvular atrial fibrillation who have normal left ventricular systolic function and a poorly controlled ventricular rate despite the use of digoxin, acute-phase beta blockade may have a harmful effect on LAA function.     

Invited Commentary on “Characteristics of non-valvular atrial fibrillation with left atrial appendage thrombus who are undergoing appropriate oral anticoagulation therapy”

The International Journal of Cardiovascular Imaging -     

Derivation and validation of E/e′ ratio as a parameter in the evaluation of left atrial appendage thrombus formation in patients with nonvalvular atrial fibrillation

We sought to determine and prospectively validate, with concomitantly performed transthoracic (TTE) and transesophageal echocardiograms (TEE), a TTE-assessed E/e′ threshold that can be useful in predicting left atrial appendage (LAA) thrombus in patients with nonvalvular atrial fibrillation (NVAF). The retrospective derivation cohort was comprised of 297 patients with NVAF with TTE performed within 1 year of TEE. The validation cohort was comprised of 266 prospectively enrolled patients with TTE performed immediately prior to TEE. LAA thrombus was detected by TEE in 6.4?% of patients in both cohorts. Receiver operating characteristic (ROC) analyses demonstrated a good discriminatory capacity of lateral E/e′ in predicting LAA thrombus in the derivation cohort (AUC 0.72; CI 0.63–0.82; P?=?0.001) which was confirmed in the validation cohort (AUC 0.83; CI 0.75–0.91; P?<?0.001). In the derivation cohort, ROC curve point-coordinates identified E/e′ thresholds of both 9.0 and 8.0 to be associated with 100?% sensitivity, with specificities of 36 and 30?%, respectively. An E/e′ threshold of ≥8 was selected a priori for prospective validation, and was associated with 100?% sensitivity and 41?% specificity for LAA thrombus, with positive and negative predictive values of 10 and 100?%, respectively, and positive and negative likelihood ratios of 1.69 and 0, respectively. We determined and validated an E/e′ threshold of 8 as a highly sensitive and useful parameter that can aid in identifying patients at very low risk for LAA thrombus and potentially obviate the need for a TEE prior to electrophysiology procedures and restoration of sinus rhythm.     

Changes in mitral valve geometry after percutaneous valve repair with the MitraClip® System

The International Journal of Cardiovascular Imaging - The aim of our study was to assess the anatomical changes of the mitral valve apparatus after percutaneous repair with the MitraClip®...     

Mechanical concordance between left atrium and left atrial appendage in nonvalvular atrial fibrillation: can it be exploited to avoid transesophageal echocardiography prior to electrical cardioversion during Covid-19 pandemic?

The International Journal of Cardiovascular Imaging - Transesophageal echocardiography (TEE) is the gold standard for assessing left atrial appendage (LAA) mechanic and thrombosis (LAAT); however,...     

Is walking endurance associated with activity and participation late after stroke??

Purpose.?After stroke, impaired walking ability may affect activity and participation. The aim was to investigate whether self-reported activity and participation were associated with walking endurance late after stroke.

Method.?A non-randomised sample of 31 persons with a mean age of 59.7 years and time since stroke of 7–10 years was studied. Walking endurance was measured by the 6-minute walk test (6MWT). Self-reported activity and participation were measured by the Physical Activity Scale for the Elderly and the Stroke Impact Scale. Relationships were analysed with linear regression.

Results.?A regression model including activities of daily living and 6MWT explained 44%%, mobility and 6MWT explained 25%% and a model including physical activity level and 6MWT explained 21%% of the variation in activity. Regarding participation, the explanatory level of the model of participation and 6MWT was 30%%.

Conclusions.?Walking distance several years after stroke was partly associated with self-reported difficulties in activity and participation.     

Two patients subdued with a TASER® device: cases and review of complications

In the United States, an increasing number of law enforcement agencies have employed the use of TASER® (TASER International Inc., Scottsdale, AZ) devices to temporarily immobilize violent subjects. There are reports in the lay press of adverse outcomes occurring in patients on whom TASER® devices have been deployed. Rhabdomyolysis has been associated with patients sustaining a TASER® shock, with a 1% incidence rate in subjects subdued with earlier versions of the device and then brought to the Emergency Department (ED). We present the cases of 2 patients who were seen in our ED after exhibiting violent behavior and receiving TASER® shocks. Both were hospitalized and received treatment for mild rhabdomyolysis. Both patients had multiple other characteristics that have been found to have an association with the development of rhabdomyolysis, in addition to the shocks they received. A review and discussion of the available medical literature on the subject follows, describing several complications that have been documented in patients after receiving TASER® shocks. Although a direct link between the TASER® and the reported adverse effects has not been established, patients who undergo restraint via this device frequently have pre-existing conditions or have exhibited behavior that places them at risk for the development of those effects. Such awareness of these possible complications is vital because the evaluation and management of patients developing adverse effects after these events will commonly occur in the ED.     

Non-contrast cardiac CT immediately after percutaneous coronary intervention: does it predict the risk of left ventricular remodeling in patients with ST-elevation myocardial infarction?

To assess the clinical utility of non-contrast cardiac CT (CCT) immediately after successful percutaneous coronary intervention (PCI) for predicting the risk of left ventricle (LV) remodeling in the management of patients with acute myocardial infarction (AMI), 35 patients with AMI underwent non-contrast CCT immediately after PCI. Volume and transmural extent of myocardial delayed enhancement (DE) were assessed on non-contrast CCT. Serial echocardiography and serologic biomarkers were evaluated at baseline and at 2 and 12 months after AMI. Based on an increase in left ventricular end-diastolic volume (LVEDV) ≥20?% at 2 months, patients were classified into two groups: LV remodeling (group 1, n?=?14) and no LV remodeling (group 2, n?=?21). Clinical characteristics, imaging parameters, and serologic biomarkers were compared between the two groups. Higher incidence of hypertension, longer time to reperfusion, and higher Killip classification at admission were observed for group 1 than for group 2, but these differences were not statistically significant (P?>?0.05). Greater volume and transmural extent of DE on non-contrast CCT and poorer resolution of ST-segment elevation on ECG were observed in group 1 compared to group 2, but these results were not statistically significant (P?>?0.05). Measurement of biochemical markers showed that probrain natriuretic peptide (proBNP), initial high sensitivity C reactive protein (hs-CRP), and maximum troponin T level were significantly higher in group 1 than in group 2 (P?<?0.05) at 2 months. Based on the trend of greater volume and transmural extent of DE in group 1 compared to group 2, non-contrast CCT immediately after PCI, in combination with serologic biomarkers (proBNP, hs-CRP, and troponin T) might be useful for managing patients with AMI.     

Relationship between intra-operative vein graft treatment with DuraGraft® or saline and clinical outcomes after coronary artery bypass grafting

ABSTRACT

Background: Saphenous vein grafts (SVGs) remain the most often used conduits for coronary bypass grafting (CABG). Progressive intimal hyperplasia contributes to vein-graft disease and vein-graft failure (VGF). We compared the impact of intraoperative preservation of SVGs in a storage solution (DuraGraft®) versus heparinized saline on VGF-related outcomes after CABG.

Methods: From 1996 to 2004, 2436 patients underwent isolated CABG with ≥ 1 SVG. SVGs were consecutively treated with DuraGraft in 1036 patients (2001?2004) and heparinized saline in 1400 patients (1996?1999). Short- (< 30 days) and long-term (≥ 1000 days) outcomes were assessed using repeat revascularization (primary end point), and major adverse cardiac events (MACE) consisting of the composite of death, nonfatal myocardial infarction, or repeat revascularization.

Results: Mean follow-up in the DuraGraft group was 8.5 ± 4.2 years and 9.9 ± 5.6 years in controls. Short-term event rates were low and generally did not differ between groups. DuraGraft was associated with a 45% lower occurrence of nonfatal myocardial infarction after 1000 days (hazard ratio 0.55, 95% CI 0.41?0.74; P < 0.0001). There was 35% and 19% lower long-term risk for revascularization (HR 0.65, 95% CI 0.44?0.97; P = 0.037) and MACE (HR 0.81, 95% CI 0.70?0.94; P = 0.0051), respectively, after DuraGraft. Mortality was comparable between both groups at 1, 5, and 10 years. There was no statistically significant association between DuraGraft exposure and time to death starting at 30 or 1000 days (HR 0.91, 95% CI 0.76?1.09; P = 0.29).

Conclusion: In this study, intraoperative treatment of SVGs with DuraGraft was associated with a lower risk of long-term adverse events suggesting that efficient intraoperative SVG treatment may reduce VGF-related complications post-CABG. These data warrant randomized clinical trials to validate these findings.     

A Case of Neurologically Intact Survival after 2 hours and 50 minutes of Euthermic Cardiac Arrest Treated with Mechanical CPR and Intra-arrest Percutaneous Coronary Intervention

We report a case of a 56 year old male in ventricular fibrillation (VF) cardiac arrest for a total of 2?hours and 50?minutes who was diagnosed with ST elevation myocardial infarction (STEMI) during a brief 10?min period of return of spontaneous circulation (ROSC). The patient underwent successful percutaneous coronary intervention (PCI) while receiving mechanical chest compressions for ongoing VF. Our case demonstrates the potential for neurologically intact survival in VF cardiac arrest patients despite prolonged periods of VF who are treated with mechanical CPR and intra-arrest PCI.