Coarse fibrillatory waves in atrial fibrillation predict success of electrical cardioversion

Background

To determine whether the presence of “coarse” fibrillatory waves (Fw) seen on surface ECGs of patients with persistent atrial fibrillation (AF) predict maintenance of sinus rhythm (SR) at 6 weeks after electrical cardioversion (ECV).

Methods

Preprocedure ECGs from 94 consecutive patients with persistent AF scheduled to undergo ECV at a single centre were classified as having coarse Fw (≥0.1 mV) or fine Fw (<0.1 mV) in leads II or V₁. The primary outcome was ECG rhythm at 6‐week clinical follow‐up. Demographic and echocardiographic data were also collected.

Results

Thirty‐two patient ECGs (34%) had coarse Fw on baseline ECG in either or both leads II or V₁ with no significant differences in baseline demographics compared to those patients with fine Fw. At 6 weeks post‐ECV, in the coarse Fw group 72% of patients maintained SR vs. 42% in the fine Fw group (χ², p = .006) with the odds ratio (OR) of maintaining SR at 6 weeks in the presence of coarse Fw being 3.5 (95% CI: 1.4–8.9, p = .007). Across the overall study population, there were no other significant univariate predictors of SR at 6 weeks post‐ECV.

Conclusion

Classifying persistent AF using the maximal Fw amplitude on a surface ECG is a simple and reproducible method of predicting medium‐term success of ECV, independent of traditional risk factors.

     

Fine versus coarse atrial fibrillation in rheumatic mitral stenosis: The impact of aging and the clinical significance

Background

Atrial fibrillation (AF) as the most rhythm disturbance in patients with rheumatic mitral stenosis (MS), is classified in to coarse and fine subtypes according to the height of fibrillatory wave amplitude. The aim of this study is to identify the factors associated with the presence of fine versus coarse morphology in patients with rheumatic MS.

Methods

In this cross‐sectional study, patients with confirmed diagnosis of severe rheumatic MS admitted between March 2013 and March 2017 were screened. Patients were categorized to sinus rhythm (SR) and AF rhythm (coarse and fine subtypes) groups according to the admission electrocardiogram. The association between various clinical and echocardiographic factors and the development of fine versus coarse AF were examined.

Results

Among 754 patients with the diagnosis of rheumatic MS, 288 (198 female) were found to have AF (38%). Among them 206 (71.5%), and 82 (28.5%) patients had fine and coarse morphology respectively. Patient in these two groups were quite similar in terms of echocardiographic parameters and comorbidities. However, patients with fine morphology AF were significantly older. (p‐Value=.007).

Conclusion

Coarse morphology of AF is common in patients with rheumatic MS. While echocardiographic or most clinical parameters do not seem to associate with the occurrence of coarse or fine morphology, age seems to be the only independent factor correlated with the presence of fine subtype of AF in this population.

     

New insights into the clinical signs of supraventricular tachycardia: The “sign of lace‐tying”

Background

Supraventricular tachycardias (SVT) are a common arrhythmia therefore an accurate diagnosis is of clinical importance. Although an ECG performed during tachycardia greatly aids diagnosis, patient history and predisposing factors also improve diagnostic accuracy.

Methods

This prospective study included 100 consecutive patients undergoing electrophysiological study for SVT with the aim to reassess their clinical characteristics and describe frequent predisposing factors, such as the “sign of lace‐tying” that to our knowledge has not previously been reported. Each patient completed an extensive questionnaire (70 questions) during their hospital stay.

Results

Our series comprised: 67% of patients with atrioventricular nodal reentrant tachycardia (AVNRT); 24% with an accessory pathway; and 9% presented atrial tachycardia. Half of the population were male and 29% of the cohort presented hypertension. Syncope during tachycardia appeared in 15% of patients, dizziness in 52% and thoracic pain in 59%. We encountered a predisposing risk factor for SVT in 53% of cases; with 32% exhibiting an anteflexion of the trunk termed the “sign of lace‐tying.” Data also showed that younger patients tended to present AVRT and regular pounding in the neck appeared only in patients with AVNRT.

Conclusions

Overall, our study has highlighted the importance of considering clinical signs and patient characteristics both before and during SVT for the precise diagnosis of paroxysmal SVT. Furthermore, 32% of patients presented the “sign of lace‐tying” or body position change before SVT, implying a diagnosis of SVT.

     

The prognostic significance of early and late right precordial lead (V4R) ST‐segment elevation in patients with acute anterior myocardial infarction

Background

The predictive significance of ST‐segment elevation (STE) in lead V₄R in patients with anterior ST‐segment elevation myocardial infarction (STEMI) has not been well‐understood. In this study, we evaluated the prognostic value of early and late STE in lead V₄R in patients with anterior STEMI.

Methods

A total 451 patients with anterior STEMI who treated with primary percutaneous coronary intervention (PPCI) were prospectively enrolled in this study. All patients were classified according to presence of STE (>1 mm) in lead V₄R at admission and/or 60 min after PPCI. Based on this classification, all patients were divided into three subgroups as no V₄R STE (Group 1), early but not late V₄R STE (Group 2) and late V₄R STE (Group 3).

Results

In‐hospital mortality had higher rates at group 2 and 3 and that had 2.1 and 4.1‐times higher mortality than group 1. Late V₄R STE remained as an independent risk factor for cardiogenic shock (odds ratio [OR] 2.6; 95% confidence interval [CI] 1.9–4.3; p < .001) and in‐hospital mortality (OR 2.3; 95% CI 1.8–4.1; p < .001). The 12‐month overall survival for group 1, 2, and 3 were 91.1%, 82.4%, and 71.4% respectively. However, the long‐term mortality also had the higher rate at group 3; late V₄R STE did not remain as an independent risk factor for long‐term mortality (OR 1.5; 95% CI 0.8–4.1; p: .159).

Conclusion

Late V₄R STE in patients with anterior STEMI is strongly associated with poor prognosis. The record of late V₄R in patients with anterior STEMI has an important prognostic value.

     

Efficacy and safety of intravenous vernakalant for the rapid conversion of recent‐onset atrial fibrillation: A meta‐analysis

Background

Atrial fibrillation is a common cardiac arrhythmia with increasing prevalence in the aging population. It is a major cause of emergency department visits worldwide. Vernakalant, a relatively new antiarrhythmic drug with selectively preferential effects on the atrial tissue is currently used in many European countries for the termination of recent‐onset atrial fibrillation. Presently, the drug is still not approved by the United States Food and Drug Administration due to safety concerns. We evaluate the efficacy and safety of vernakalant for the conversion of recent‐onset atrial fibrillation or atrial flutter into normal sinus rhythm (NSR).

Methods

PubMed/MEDLINE (1993–2017), the Cochrane Central Register of Controlled Trials (2000–2017), and reference lists of relevant articles were searched for randomized controlled trials (RCTs) comparing vernakalant to a control drug and extracted subsequently.

Results

Nine RCTs were identified and included in the meta‐analysis. Pooled analysis of events extracted for a total of 1421 patients with recent‐onset atrial fibrillation showed a statistically significant increase in cardioversion within 90 minutes from drug infusion (Relative Risk [RR], 6.61; 95% Confidence Interval [CI], 2.78 – 15.71; p < .00001). In terms of adverse events, vernakalant was considered safe in comparison to control drugs (RR, 0.80; 95% CI, 0.61–1.05; p = .11).

Conclusion

Vernakalant is effective for rapid conversion of recent‐onset atrial fibrillation into NSR. However, although it showed a safe profile in terms of side effects in this analysis, we are still hesitant about this conclusion and few safety issues should be addressed within specific patients’ subgroups.

     

The effect of head‐up tilt upon markers of heart rate variability in patients with atrial fibrillation

Background

Heart rate variability (HRV) analysis is uncommonly undertaken in patients with atrial fibrillation (AF) due to an assumption that ventricular response is random. We sought to determine the effects of head‐up tilt (HUT), a stimulus known to elicit an autonomic response, on HRV in patients with AF; we contrasted the findings with those of patients in sinus rhythm (SR).

Methods

Consecutive, clinically indicated tilt tests were examined for 207 patients: 176 in SR, 31 in AF. Patients in AF were compared to an age‐matched SR cohort (n = 69). Five minute windows immediately before and after tilting were analyzed using time‐domain, frequency‐domain and nonlinear HRV parameters. Continuous, noninvasive assessment of blood pressure, heart rate and stroke volume were available in the majority of patients.

Results

There were significant differences at baseline in all HRV parameters between AF and age matched SR. HUT produced significant hemodynamic changes, regardless of cardiac rhythm. Coincident with these hemodynamic changes, patients in AF had a significant increase in median [quartile 1, 2] DFA‐α2 (+0.14 [?0.03, 0.32], p < .005) and a decrease in sample entropy (?0.17 [?0.50, ?0.01], p < .005).

Conclusion

In the SR cohort, increasing age was associated with fewer HRV changes on tilting. Patients with AF had blunted HRV responses to tilting, mirroring those seen in an age matched SR group. It is feasible to measure HRV in patients with AF and the changes observed on HUT are comparable to those seen in patients in sinus rhythm.

     

Comparison of the predictive accuracy of four different ECG algorithms in identification of true ablation site for the idiopathic right ventricular outflow tract tachycardias

Background

We aimed to investigate the accuracy of four algorithms in prediction of right ventricular outflow tract (RVOT) tachycardias in patients who successfully underwent radiofrequency catheter ablation.

Methods

Four algorithms; two with easy‐applicability and having a memorable design (Dixit and Joshi), and two with more complex and detailed design (Ito and Zhang) were compared according to the predictive accuracy.

Results

Among 99 patients (mean age 36.5 ± 8.5 years, 39.4% male), there were 51 (51.5%) septal‐located and 48 (48.5%) free‐wall located RVOT tachycardia. Comparison of the predictive accuracy of the algorithms showed that Zhang (91.9%) was the best algorithm for prediction of either septal or free‐wall located tachycardia. The second best algorithm was the Ito (77.7%) compared to Dixit (75.8%) and Joshi (70.7%).

Conclusion

In patients with RVOT tachycardia, algorithms with a detailed design may predict the arrhythmia location better than the easy‐applicable algorithms.

     

Use of fragmented QRS in prognosticating clinical deterioration and mortality in pulmonary embolism: A meta‐analysis

Background

Fragmented QRS (fQRS) on electrocardiography is potentially valuable in prognosticating acute pulmonary embolism (PE). ECG is one of the first tests performed in the emergency department, quickly interpretable, noninvasive, inexpensive, and available in remote areas. We aimed to review fQRS's role in PE prognostication.

Methods

We searched MEDLINE, EMBASE, Google Scholar, Web of Science, abstracts, conference proceedings, and reference lists until October 2017. Eligible studies used fQRS to prognosticate patients for the main outcomes of death and clinical deterioration or escalation of therapy. Two authors independently selected studies, with disagreement resolved by consensus. Ad hoc piloted forms were used to extract data and assess risk of bias. We used a random‐effects model to pool relevant data in meta‐analysis with odds ratios (OR) and 95% confidence intervals (CI), while all other data were synthesized qualitatively. Statistical heterogeneity was assessed using the I² index.

Results

We included five studies (1,165 patients). There was complete agreement in study selection. fQRS significantly predicted in‐hospital mortality (OR [95% CI], 2.92 [1.73–4.91]; p < .001), cardiogenic shock (OR [95% CI], 4.71 [1.61–13.70]; p = .005), and total mortality at 2‐year follow‐up (OR [95% CI], 4.42 [2.57–7.60]; p < .001). Adjusted analyses were generally consistent with these results.

Conclusion

Although few studies have explored the current study's question, they showed that fQRS is potentially valuable in PE prognostication. fQRS should be considered as an entry, along with other clinical and ECG findings, in a PE risk score.

     

Impact of ST‐segment resolution on clinical outcome in patients with ST‐segment elevation myocardial infarction and preserved left ventricular function

Background

Patients with successful reperfusion and preserved left ventricular ejection fraction (LVEF) after ST‐segment myocardial infarction (STEMI)have always been thought to have low risk for adverse events. Great interest is focused on finding simple, noninvasive tools to refine risk stratification among them.

Objectives

We hypothesized that degree of ST‐segment resolution (STR) after STEMI can identify high‐risk group among patients with LVEF ≥ 50% following STEMI.

Methods

During the period from January to July 2017, patients with successful reperfusion of STEMI and LVEF ≥ 50% were prospectively included. Patients were divided into two groups based on the percent of ST segment resolution using single lead STR method; group I (complete STR ≥ 70%) and group II (partial STR 50%–70%). The endpoint was a composite of cardiovascular mortality, re‐hospitalization for heart failure and urgent revascularization at 30‐day.

Results

After exclusion, 110 patients were left for final analysis. No significant differences in all baseline characteristics were found between both groups. The primary endpoint occurred in seven patients (12.7%) of group I versus 17 patients (30.9%) of group II (Relative risk = 2.43, 95%CI = 1.1–5.4, p = 0.021) driven by a significant reduction in rates of re‐hospitalization due to heart failure. A multivariate logistic regression analysis showed incomplete STR to be a significant independent predictor for 30‐dayMACEs (OR 3.25, 95% CI1.2–8.83, p = 0.02) even after adjustment for location of infarction.

Conclusion

Complete STR predicts 30‐day outcome in patients with preserved LVEF following successful reperfusion of STEMI.

     

Relation between electrical and mechanical dyssynchrony in patients with left bundle branch block: An electro‐ and vectorcardiographic study

Background

Current guidelines select patients for cardiac resynchronization therapy (CRT) mainly on electrocardiographic parameters like QRS duration and left bundle branch block (LBBB). However, among those LBBB patients, heterogeneity in mechanical dyssynchrony occurs and might be a reason for nonresponse to CRT. This study assesses the relation between electrocardiographic characteristics and presence of mechanical dyssynchrony among LBBB patients.

Methods

The study included patients with true LBBB (including mid‐QRS notching) on standard 12‐lead electrocardiograms. Left bundle branch block‐induced mechanical dyssynchrony was assessed by the presence of septal flash on two‐dimensional echocardiography. Previously reported electro‐ and vectorcardiographic dyssynchrony markers were analyzed: global QRS duration (QRSD_LBBB), left ventricular activation time (QRSD_LVAT), time to intrinsicoid deflection (QRSD_ID), and vectorcardiographic QRS areas in the 3D vector loop (QRSA_3D).

Results

The study enrolled 545 LBBB patients. Septal flash (SF) is present in 52% of patients presenting with true LBBB. Patients with SF are more frequent female, have less ischemic heart disease and smaller left ventricular dimensions. In multivariate analysis longer QRSD_LBBB, QRSD_LVAT and larger QRSA_3D were independently associated with SF. Of all parameters, QRSA_3D has the best accuracy to predict SF, although overall accuracy remains moderate (59% sensitivity, 58% specificity). The predictive value of QRSA_3D remained constant in both sexes, irrespective of ischemic heart disease, ejection fraction and even when categorizing for QRSD_LBBB.

Conclusion

In LBBB patients, large QRS areas correlate better with mechanical dyssynchrony compared to wide QRSD intervals. However, the overall accuracy to predict mechanical dyssynchrony by electrocardiographic dyssynchrony markers, even when using complex vectorcardiographic parameters, remains low.

     

Marked exercise‐induced T‐wave heterogeneity in symptomatic diabetic patients with nonflow‐limiting coronary artery stenosis

Background

T‐wave heterogeneity (TWH) independently predicted cardiovascular mortality in Health Survey 2000 based on 12‐lead ECGs recorded at rest. We investigated whether TWH is elevated during exercise tolerance testing (ETT) in symptomatic diabetic patients with nonflow‐limiting coronary artery stenosis compared to control subjects without diabetes.

Methods

Cases were all patients (n = 20) with analyzable ECG recordings during both rest and ETT who were enrolled in the Effects of Ranolazine on Coronary Flow Reserve (CFR) in Symptomatic Patients with Diabetes and Suspected or Known Coronary Artery Disease (RAND‐CFR) study (NCT01754259); median CFR was 1.44; 80% of cases had CFR <2. Control subjects (n = 9) were nondiabetic patients who had functional flow reserve (FFR) >0.8, a range not associated with inducible ischemia. TWH was analyzed from precordial leads V₄, V₅, and V₆ by second central moment analysis, which assesses the interlead splay of T‐waves about a mean waveform.

Results

During exercise to similar rate‐pressure products (p = .31), RAND‐CFR patients exhibited a 49% increase in TWH during exercise (rest: 49 ± 5 μV; exercise: 73 ± 8 μV, p = .003). By comparison, in control subjects, TWH was not significantly altered (rest: 52 ± 11 μV; ETT: 38 ± 5 μV, p = .19). ETT‐induced ST‐segment depression >1 mm (p = .11) and T_peak‐T_end (p = .18) and QTc intervals (p = .80) failed to differentiate cases from controls.

Conclusions

TWH is capable of detecting latent repolarization abnormalities, which are present during ETT in diabetic patients with nonflow‐limiting stenosis but not in control subjects. The technique developed in this study permits TWH analysis from archived ECGs and thereby enables mining of extensive databases for retrospective studies and hypothesis testing.

     

Prognostic value of T‐wave morphology parameters in coronary artery disease in current treatment era

Background

The prognostic value of T‐wave morphology parameters in coronary artery disease in the current treatment era is not well established.

Methods

The Innovation to reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study included 1,946 patients with angiographically verified coronary artery disease (CAD). The study patients underwent thorough examinations including 12‐lead digital electrocardiogram (ECG) at baseline.

Results

During a follow‐up period of 73 ± 22 months, a total of 201 (10.3%) patients died. Of the study patients, 95 (4.9%) experienced cardiac death (CD) consisting of 44 (2.3%) sudden cardiac deaths (SCD) and 51 (2.6%) nonsudden cardiac deaths (NSCD), and 106 (5.4%) patients experienced noncardiac death (NCD). T‐wave morphology dispersion (TMD), T‐wave area dispersion (TWAD), and total cosine R‐to‐T (TCRT) had a significant association with CD even after adjustment with relevant clinical risk markers in the Cox regression analysis (multivariate HRs: 1.015, 95% CI 1.007–1.023, p = .0003; 0.474, 95% CI 0.305–0.737, p = .0009; 0.598, 95% CI 0.412–0.866, p = .006, respectively). When including these parameters to the clinical risk model for CD, the C‐index increased from 0.810 to 0.823 improving the discrimination significantly (integrated discrimination index [IDI] = 0.0118, 95% CI 0.0028–0.0208, p = .01). These parameters were more closely associated with NSCD (multivariate p‐values from .016 to .001) than with SCD (univariate/multivariate p‐values for TMD .015/.197 and for TCRT .012/.43).

Conclusion

T‐wave morphology parameters describing repolarization heterogeneity improve the predictive power of the clinical risk model for CD in patients with CAD in the current treatment era.

     

First‐in‐human experience of left atrial appendage occlusion with the steerable FuStar sheath

Background

Due the wide variability of left atrial appendage morphology left atrial appendage occlusion (LAAO) remains a challenging procedure. The steerable FuStar delivery sheath was designed to allow both, transseptal access and delivery of percutaneous devices. We here report the first‐in‐human experience of LAAO with the FuStar sheath.

Methods

Twenty patients (76.6 ± 8.4 years; 12 (60%) males; CHA₂DS₂‐VASc score: 5.0 ± 2) with non‐valvular fibrillation and contraindications to oral anticoagulation underwent LAAO with the LAmbre device using the FuStar steerable sheath (Lifetech Scientific Corp., Shenzhen, China) at two german centers.

Results

Successful device implantation was achieved in all patients (100%). No periprocedural complications were observed. Procedure time, fluoroscopy time, contrast media, and radiation dose were 23.4 min ± 9.2, 11.9 min ± 4.1, 96.2 mL ± 45.7, and 2718.4 cG*cm² ± 3835.3, respectively.

Conclusion

This study demonstrates the feasibility and safety of the steerable FuStar sheath for LAAO.

     

Administrative billing codes accurately identified occurrence of electrical cardioversion and ablation/maze procedures in a prospective cohort study of atrial fibrillation patients

Background

Administrative billing codes for electrical cardioversion and ablation/maze procedures may be useful for atrial fibrillation (AF) research if the codes are accurate relative to medical record documentation.

Hypothesis

Administrative billing codes accurately identify occurrence of electrical cardioversion and ablation/maze procedures in AF patients.

Methods

We studied adults ages 30 to 84 who experienced new‐onset AF between October 2001 and December 2004 in Group Health Cooperative (acquired by Kaiser Permanente in 2017), an integrated healthcare system in Washington state and northern Idaho. Using medical record review as the gold standard, we calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for 3 administrative billing codes for electrical cardioversion and 3 codes for AF ablation/maze procedures.

Results

Of 1953 study participants, during a mean (SD) of 1.5 (0.7) years of follow‐up after AF onset, 470 (24%) experienced electrical cardioversion and 44 (2%) experienced ablation/maze procedures, according to medical record review. For electrical cardioversion, individual codes had 7.7% to 76.4% sensitivity, >99% specificity, 83.7% to 96.5% PPV, and 77.3% to 93.0% NPV. Considering any of 3 codes (code 1 or code 2 or code 3) improved sensitivity to 84.9%. For ablation/maze, individual codes had 18.2% to 47.7% sensitivity, >99% specificity, 66.7% to 95.5% PPV, and >98% NPV. Considering any of 3 codes improved sensitivity to 84.1%.

Conclusions

Administrative billing data accurately identified electrical cardioversion and ablation/maze procedures and can be used instead of medical record review. Our findings apply to healthcare settings with available administrative billing databases.

     

Prognostic value of positive T wave in lead aVR in patients with non‐ST segment myocardial infarction

Background

Lead aVR provides prognostic information in various settings in patients with ischemia. We aim to investigate the role of a positive T wave in lead aVR in non‐ST segment myocardial infarction (NSTEMI).

Methods

In a prospective cohort study, we included 400 patients with NSTEMI. Presentation electrocardiogram (ECG) was investigated for presence of a positive T wave as well as ST segment elevation (STE) in aVR and study variables were compared. Predictors of primary outcome defined as hospital major adverse cardiovascular events (MACE) and secondary outcome, defined as three‐vessel coronary disease and/or left main coronary artery stenosis (3VD/LMCA) stenosis in angiography, were determined in multivariate logistic regression analysis.

Results

Patients with a positive T wave in aVR were significantly older and were more likely to be female. Left ventricular ejection fraction was significantly lower in patients of positive T group. Positive T group was more likely to have 3VD/LMCA stenosis (58.3% vs. 19.8%, p < .001). The prevalence of a positive T wave in aVR was significantly higher in MACE group (54.9 % vs. 24.8%, p < .001). However, in multivariate analysis, it was not an independent predictor of MACE (OR: 1.083 95% CI: [0.496–2.365], p: .841). Though, it was independently associated with presence of 3VD/LMCA stenosis (OR: 3.747 95% CI: [2.058–6.822], p < .001).

Conclusion

Though positive T wave in lead aVR was more common in patients with MACE; it was not an independent predictor. Additionally, a positive T wave in aVR was an independent predictor of 3VD/LMCA stenosis in NSTEMI.

     

The sensitivity of 38 heart rate variability measures to the addition of artifact in human and artificial 24‐hr cardiac recordings

Background

Artifact is common in cardiac RR interval data derived from 24‐hr recordings and has a significant impact on heart rate variability (HRV) measures. However, the relative impact of progressively added artifact on a large group of commonly used HRV measures has not been assessed. This study compared the relative sensitivity of 38 commonly used HRV measures to artifact to determine which measures show the most change with increasing increments of artifact. A secondary aim was to ascertain whether short‐term and long‐term HRV measures, as groups, share similarities in their sensitivity to artifact.

Methods

Up to 10% of artifact was added to 20 artificial RR (ARR) files and 20 human cardiac recordings, which had been assessed for artifact by a cardiac technician. The added artifact simulated deletion of RR intervals and insertion of individual short RR intervals. Thirty‐eight HRV measures were calculated for each file. Regression analysis was used to rank the HRV measures according to their sensitivity to artifact as determined by the magnitude of slope.

Results

RMSSD, SDANN, SDNN, RR triangular index and TINN, normalized power and relative power linear measures, and most nonlinear methods examined are most robust to artifact.

Conclusion

Short‐term time domain HRV measures are more sensitive to added artifact than long‐term measures. Absolute power frequency domain measures across all frequency bands are more sensitive than normalized and relative frequency domain measures. Most nonlinear HRV measures assessed were relatively robust to added artifact, with Poincare plot SD1 being most sensitive.

     

The analysis of the parameters of 24‐hr ECG Holter monitoring in patients with blood neoplasms undergoing high‐dose chemotherapy and stem cell transplantation

Background

Hematopoietic stem cell transplantation (HSCT) is a widely used procedure in the treatment of malignant diseases, including blood neoplasms and has increased survival in hematological diseases. The aim of the study was to analyze parameters of 24‐hr ECG monitoring in patients with selected blood neoplasms in whom the procedure of hematopoietic stem cell transplantation was performed.

Methods

The study group consisted of 64 adults diagnosed with hematologic cancer qualified for HSCT with the previous high dose chemotherapy (HDC). In all patients 24‐hr Holter monitoring was carried out twice. First examination took place prior to the HSCT procedure, and the second after finishing the procedure of HSCT.

Results

The minimal and mean heart rate (HR min and HR max) from 24‐hr ECG recording was statistically significantly higher after the transplantation in comparison with the first test. The number of premature ventricular complexes (PVCs) was higher in the test after HSCT. In the second examination there was significantly higher percentage of premature ventricular complexes, incidents of tachycardia, and Mobitz type 1 second degree atrioventricular block. In regression analysis, in a group of patients with blood neoplasms after HSCT and HDC, administration of cyclophosphamide, fludarabine and total body irradiation were independent risk factors for electrocardiographic abnormalities in 24‐hr Holter monitoring, that is, the increase in HR min, HR mean and PVCs.

Conclusion

In patients with blood neoplasms undergoing HSCT more electrocardiographic abnormalities may be found after this procedure in comparison with the 24‐hr Holter monitoring before transplantation.

     

S‐R difference in V1‐V2 is a novel criterion for differentiating the left from right ventricular outflow tract arrhythmias

Aim

The correct estimation of the VA origin as RVOT or LVOT results in reduced ablation duration reduced radiation exposure and decreased number of vascular access. In our study, we aimed to detect the predictive value of S‐R difference in V1‐V2 for differentiating the left from right ventricular outflow tract arrhythmias.

Methods

We included 123 patients with symptomatic frequent premature ventricular outflow tract contractions who underwent successful catheter ablation (70 male, 53 female; mean age 46.2 ± 13.9 years, 61 RVOT, 62 LVOT origins). S‐R difference in V1‐V2 was calculated with this formula on the 12‐lead surface ECG: (V1S + V2S) – (V1R + V2R). Conventional ablation was performed in 101 (82.1%) patients, CARTO electroanatomic mapping system was used in 22 (17.9%) patients.

Results

V1‐2 SRd was found to be significantly lower for LVOT origins than RVOT origins (p < .001). The cutoff value of V1‐2 SRd obtained by ROC curve analysis was 1.625 mV for prediction of RVOT origin (sensitivity: 95.1%, specificity: 85.5%, positive predictive value: 86.5%, negative predictive value: 94.5%). The area under the curve (AUC) was 0.929 (p < .001).

Conclusion

S‐R difference in V1‐V2 is a novel and simple electrocardiographic criterion for accurately differentiating RVOT from LVOT sites of ventricular arrhythmia origins. The use of this simple ECG measurement could improve the accuracy of OTVA localization, could be beneficial for decreasing ablation duration and radiation exposure. Further studies with larger patient population are needed to verify the results of this study.

     

Ultra‐short heart rate variability recording reliability: The effect of controlled paced breathing

Background

Recent studies have reported that Heart Rate Variability (HRV) indices remain reliable even during recordings shorter than 5 min, suggesting the ultra‐short recording method as a valuable tool for autonomic assessment. However, the minimum time‐epoch to obtain a reliable record for all HRV domains (time, frequency, and Poincare geometric measures), as well as the effect of respiratory rate on the reliability of these indices remains unknown.

Methods

Twenty volunteers had their HRV recorded in a seated position during spontaneous and controlled respiratory rhythms. HRV intervals with 1, 2, and 3 min were correlated with the gold standard period (6‐min duration) and the mean values of all indices were compared in the two respiratory rhythm conditions.

Results

rMSSD and SD1 were more reliable for recordings with ultra‐short duration at all time intervals (r values from 0.764 to 0.950, p < 0.05) for spontaneous breathing condition, whereas the other indices require longer recording time to obtain reliable values. The controlled breathing rhythm evokes stronger r values for time domain indices (r values from 0.83 to 0.99, p < 0.05 for rMSSD), but impairs the mean values replicability of domains across most time intervals. Although the use of standardized breathing increases the correlations coefficients, all HRV indices showed an increase in mean values (t values from 3.79 to 14.94, p < 0.001) except the RR and HF that presented a decrease (t = 4.14 and 5.96, p < 0.0001).

Conclusion

Our results indicate that proper ultra‐short‐term recording method can provide a quick and reliable source of cardiac autonomic nervous system assessment.

     

Diagnostic accuracy of instantaneous wave free‐ratio in clinical practice

Aims

To evaluate the correlation between iFR and FFR in real‐world clinical practice.

Methods and Results

Retrospective, single‐centre study of 229 consecutive pressure‐wire studies (n_p = 158). Real‐time iFR and FFR measurements were performed for angiographically borderline stenoses. Functionally significant stenoses were defined as iFR <0.86 or FFR ≤0.80. An iFR between 0.86 and 0.93 was considered within the grey zone (Hybrid approach). Median iFR and FFR (IQR) were 0.92 (0.87‐0.95) and 0.83 (0.76‐0.89), respectively. Pearson's correlation coefficient was 0.75 (P < 0.001). Bland‐Altman plot showed a mean difference between iFR and FFR that remained consistent throughout the range of values. The optimal iFR cutoff was 0.91—sensitivity 80%, specificity 82% with ROC area under curve of 89%. Using the Hybrid iFR‐FFR strategy, we demonstrated high accuracy of iFR results—sensitivity 95%, specificity 96%, PPV 95%, and NPV 96%. In addition, this method would have avoided adenosine in 56% of patients. Mean follow‐up period was 17.2 (±3.4) months. All‐cause mortality was 3.2% (n_p = 5) and repeat intervention was required in six lesions (2.6%).

Conclusions

This study demonstrates that iFR is a valuable adjunct to FFR using the Hybrid iFR‐FFR strategy in a real‐world population. The use of adenosine may be avoided in about half the cases.