Serum troponin testing in patients with paroxysmal supraventricular tachycardia: outcome after ED care

The Role of Troponin Testing in Patients with Supraventricular Tachycardia, Systematic Review and Meta-Analysis

BACKGROUND

Supraventricular tachycardia (SVT) is commonly evaluated in the emergency department (ED). While troponin has been shown to be elevated in SVT, its usefulness for predicting coronary artery disease and future adverse cardiovascular outcomes has not been shown.

OBJECTIVES

We aimed to evaluate the prognostic utility of troponin measurement as part of SVT management in the ED.

METHODS

We performed a literature search in the PubMed and Scopus databases from inception to August 30, 2023, including all studies reporting troponin measurements in adult patients (age > 18 years) presenting to the ED with supraventricular tachycardia. The primary outcome of interest for this study was the prevalence of elevated troponin in patients with SVT. Secondary outcomes included the prevalence of major adverse cardiac events (MACE) and additional cardiac testing with significant findings.

RESULTS

We included 7 studies (500 patients) in our analysis. Six studies reported the number of patients with SVT and elevated troponin, with a pooled prevalence of 46% (95% CI 27-66%, I2 93%). The pooled prevalence of all MACE in our study was 6% (95% CI 1-25%), while the prevalence for MACE among patients with elevated serum troponin levels was 11% (95% CI 4-27%).

CONCLUSIONS

Troponin levels are frequently ordered for ED patients with SVT and are often elevated. However, this review suggests that they have low prognostic value in predicting MACE.

Symptom burden guiding invasive electrophysiological study in paroxysmal supraventricular tachycardia: The believe SVT registry

BACKGROUND AND OBJECTIVE

Patients with palpitations clinically suggestive of paroxysmal supraventricular tachycardia (PSVT) are often managed conservatively until ECG-documentation of the tachycardia, leading to high impact on life quality and healthcare resource utilization. We evaluated results of electrophysiological study (EPS), and ablation when appropriate, among these patients, with special focus on gender differences in management.

METHODS

BELIEVE SVT is a European multicenter, retrospective registry in tertiary hospitals performing EPS in patients with palpitations, without ECG-documentation of tachycardia or preexcitation, and considered highly suggestive of PSVT by a cardiologist or cardiac electrophysiologist. We analyzed clinical characteristics, results of EPS and ablation, complications, and clinical outcomes during follow-up.

RESULTS

Six-hundred eighty patients from 20 centers were included. EPS showed sustained tachycardia in 60.9% of patients, and substrate potentially enabling AVNRT in 14.7%. No major/permanent complications occurred. Minor/transient complications were reported in 0.84% of patients undergoing diagnostic-only EPS and 1.8% when followed by ablation. During a 3.4-year follow-up, 76.2% of patients remained free of palpitations recurrence. Ablation (OR: 0.34, P < .01) and male gender (OR: 0.58, P = .01) predicted no recurrence. Despite a higher female proportion among patients with recurrence, (77.2% vs 63.5% among those asymptomatic during follow-up, P < .01), 73% of women in this study reported no recurrence of palpitations after EPS.

CONCLUSIONS

EPS and ablation are safe and effective in preventing recurrence of nondocumented palpitations clinically suggestive of PSVT. Despite a lower efficacy, this strategy is also highly effective among women and warrants no gender differences in management.

Prognostic value of cardiac troponin in elderly patients with paroxysmal supraventricular tachycardia: A multicenter study

BACKGROUND

An elevated level of cardiac troponin I (cTnI) frequently accompanies an episode of supraventricular tachycardia (SVT). However, the predictive value of cTnI in elderly SVT patients has not been examined.

METHODS

We collected the electronic medical records of elderly SVT patients (over 65 years old) who visited four Taiwanese emergency departments over a 2-year period. The patients who underwent cTnI testing were included in the cohort and further categorized based on their cTnI results (positive or negative). The study's primary outcomes were the 5-year risks of major adverse cardiovascular events (MACE) and SVT recurrence.

RESULTS

One hundred and twenty-four patients met the inclusion criteria. Of these patients, 39 (31.5%) had a positive cTnI result, and 85 (68.5%) had a negative cTnI result. Patients with a positive cTnI result were older (p = 0.029) and had a longer hospital stay (p = 0.023) than those with a negative cTnI result. Multivariate analysis showed that age > 75 years (OR = 2.41; 95% CI 1.07-5.45; p = 0.034) was an independent predictor for cTnI elevation. In the survival analysis, no difference in the incidence of five-year MACE (p = 0.656) was observed between the cTnI-positive and cTnI-negative groups. Multivariate analysis revealed that a history of coronary artery disease was the only significant independent risk factor for MACE (HR = 4.30; 95% 95% CI 1.41-13.05; p = 0.010). For SVT recurrence, the multivariate analysis revealed that previous SVT (HR = 3.37; 95% CI 1.53-7.39; p = 0.002), smoking history (HR = 2.32; 95% CI 1.03-5.24; p = 0.043), and RFA treatment (HR = 0.20; 95% CI 0.06-0.65; p = 0.008) were significant independent predictors.

CONCLUSIONS

An increased cardiac troponin level may not effectively indicate the risk of MACE in elderly SVT patients. Physicians might want to be cautious when interpreting troponin test results for this specific patient group.

Prognostic value of cardiac troponin in dialysis patients with paroxysmal supraventricular tachycardia

A rise in cardiac troponin I (cTnI) is common in supraventricular tachycardia (SVT). While troponin elevation in SVT is thought to be a predictor of future adverse events in patients with prior coronary artery disease, the prognostic significance of cTnI in end-stage kidney disease (ESKD) patients with SVT are not known. We aimed to examine the prognostic significance of cTnI in ESKD patients presenting with SVT in the emergency department. This was a retrospective, multiple-center observational study utilizing regularly collected electronic medical records. We screened electronic medical records of all dialysis patients presenting to the emergency departments in 5 hospitals over 12 years with SVT. These patients were divided into whether cTnI was tested, and were further stratified into the cTnI-positive and cTnI-negative groups. The primary outcome of the study was the 3-year risk of major adverse cardiovascular events (MACE). Sixty-two patients were qualified for inclusion. Fifty-seven patients (91.9%) were tested for cTnI, and 5 patients were not. Patients with the cTnI test were older (P = .03) and had a longer length of hospital stay (P < .001). Forty-seven patients (82.5%) had a positive result, and 10 (17.5%) had a negative result. A history of hypertension (P = .013) and decreased left ventricular ejection fraction (P = .048) were the independent predictors of cTnI elevation. After a mean follow-up period of 20.6 ± 14.7 months, there were no differences in 3-year MACE between patients with or without elevated cTnI levels in Kaplan-Meier analysis (P = .34). A history of coronary artery disease was the only independent predictor of 3-year MACE (P = .017). Through the subgroup analysis, a history of coronary artery disease (HR 2.73; CI 1.01-7.41; P = .049) remained an independent risk factor for 3-year MACE in patients with elevated cTnI levels. A large proportion (82.5%) of troponin elevation was observed in ESKD patients with SVT, but it had a poor correlation with MACE.

The correlation of 30- and 90-day mortality rates with Hs-troponin I values measured in patients diagnosed with paroxysmal supraventricular tachycardia in emergency service

Background:

This study aims to determine the relationship between troponin levels and 30- and 90-day mortality rates in patients who applied to emergency service with paroxysmal supraventricular tachycardia.

Materials and methods:

The data of our study were obtained from the retrospective screening of the files of 321 patients who applied to the emergency department between 1 January 2015 and 31 December 2016 with International Classification of Diseases diagnosis with I47.1 (supraventricular tachycardia). Unstable patients, patients under 18 years, and patients with comorbidities that could increase troponin levels did not participate in the study. A total of 159 patients diagnosed with paroxysmal supraventricular tachycardia were included in the study. These patients’ files were examined, and their examination and anamnesis information at the time of admission to hospital, demographic characteristics, and applied treatments were analyzed. The 30- and 90-day mortality rates of the patients were examined.

Results:

The study was carried out with 159 patients. Troponin was positive in 25 (15.7%) cases, while it was negative in 134 (84.3%) cases. There was no significant difference between the two groups in terms of 30- and 90-day mortality rates. Coronary artery disease was found to be higher in patients with positive troponin than patients with negative troponin.

Conclusion:

No significant difference was found between patients with positive troponin values compared to patients with negative troponin values in terms of 30- and 90-day mortality rates. We believe that prospective observational studies or large-scale retrospective studies will better elucidate this issue.

The role of coronary computed tomography angiography in evaluation of high troponin patients with narrow-complex supraventricular tachycardia

Aim:

The aim of this study was to investigate the relation of high-sensitive cardiac troponin T (hs-cTnT) elevation with characteristics of supraventricular tachycardia (SVT) episode (duration and maximum heart rate) and coronary computed tomography angiography (CCTA) findings in patients with SVT who presented to the emergency room with palpitation.

Methods:

This retrospective, single-center, noninvasive study included all patients aged between 18 years and 65 years who presented to the emergency department due to narrow-complex SVT and underwent CCTA to rule out coronary artery disease (CAD) due to elevation of hs-cTnT and reverted back to sinus rhythm after intravenous adenosine. The first, second, and the maximum hs-cTnT levels were obtained from the database. The patients were classified into normal coronaries, nonobstructive CAD, and obstructive CAD according to findings of the CCTA. The findings of the groups were compared.

Results:

Eighty-five patients were enrolled in the study. Of them, 21 (26%) patients were female. Sixty-three patients (74%) had normal coronary arteries as per CCTA results, whereas 22 patients (22%) had nonobstructive CAD and two patients (2%) had obstructive CAD. The groups did not differ statistically in respect to hs-cTnT measurements, duration of the arrhythmia, and maximum heart rate at SVT episode. There was no significant statistical correlation between hs-cTnT and the study parameters except the maximum heart rate.

Conclusion:

Cardiac troponins may increase in patients with paroxysmal SVT irrespective of the presence of coronary lesions, and the CCTA may not be an appropriate investigation in the differential diagnosis of paroxysmal SVT with elevated hs-cTnT.

Prognostic value of cardiac troponin levels in patients presenting with supraventricular tachycardias

BACKGROUND

An association between paroxysmal supraventricular tachycardias (PSVT) and elevated cardiac troponin I (cTnI) has been reported in small studies, even in the absence of significant coronary artery or structural heart disease. We sought to explore the prognostic significance of elevated cTnI among patients presenting with PSVT.

METHODS

This is a retrospective single-center observational study conducted between January 2014 and Decemebr 2016. 165 patients (60% men, mean age 55 ± 17 year-old) with an acute episode of regular supraventricular tachyarrhythmia were admitted to the emergency department at Rambam Medical Center. 131 patients had at least one serum cTnI value measured. Of those, 57 had a positive result, defined as serum cTnI of more than 0.028 ng/dL.

RESULTS

Multivariate analysis showed that heart rate > 150 beats per minute (bpm) on admission (OR = 3.9; 95% CI 1.1.6-9.5; p < 0.003) and history of coronary artery disease (CAD) (OR = 3.4; 95% CI 1.2-10.1; p = 0.026) were the only independent predictors of cTnI elevation. After mean follow-up period of 23 ± 7 months, the combined primary outcome of death, coronary intervention (PCI) or myocardial infarction (MI) occurred in 7 patients (12.3%) out of 57 patients with positive cTnI and in zero patients with negative cTn (p = 0.002). Cox proportional hazard model showed that elevated cTnI on admission was an independent predictor of adverse outcomes only in patients with known coronary artery disease (CAD) (HR = 3.3, p = 0.05).

CONCLUSION

Elevated cTnI among patients presenting with PSVT appears to have prognostic significance only in patients with history of CAD. In this patient group elevated cTnI is associated with increased risk of adverse cardiac outcomes. We therefore believe serum cTnI should be measured selectively, such as in patients with symptoms of ischemic chest pain and a high pretest likelihood of having CAD.

Correlation of circulating pro-angiogenic miRNAs with cardiotoxicity induced by epirubicin/cyclophosphamide followed by docetaxel in patients with breast cancer

OBJECTIVE

This study aimed to evaluate predictive value of 14 pro-angiogenic miRNAs for cardiotoxicity induced by epirubicin/cyclophosphamide follow by docetaxel (EC-D) in breast cancer (BC) patients.

METHODS

Three hundred and sixty-three BC patients receiving EC-D neoadjuvant chemotherapy were consecutively enrolled in this prospective cohort study. Peripheral blood sample was obtained from each patient, and plasma was separated. The expressions of 14 pro-angiogenic miRNAs, cardiac troponin I (cTnI) and N-terminal pro brain natriuretic peptide (NT-proBNP) were evaluated. Left ventricular ejection fraction (LVEF) level at C0, the end of 4 cycles of EC chemotherapy (C4), the end of 4 cycles of docetaxel treatment (C8), 3rd months (M3), 6th months (M6), 9th months (M9) and 12th months (M12) after surgery were assessed.

RESULTS

LVEF decreased at C4, C8, M3, M6, M9 and M12 compared with C0, and the total cardiotoxicity incidence was 5.2%. Additionally, the levels of let-7f, miR-17-5p, miR-20a, miR-126, miR-210 and miR-378 were reduced in cardiotoxicity patients. Multivariate logistic regression revealed that miR-17-5p and miR-20a were independently predictive factors for less cardiotoxicity. Receiver operating characteristics (ROC) curve displayed a satisfactory predictive value for lower cardiotoxicity risk with area under curve (AUC) of 0.842 of the combination of the miR-17-5p and miR-20a expressions. In addition, let-7f,miR-126, miR-210 and miR-378 levels negatively correlated with cTnI expression, and let-7f and miR-130a expressions reversely correlated with NT-proBNP level.CONLUSIONS: miR-17-5p and miR-20a could be served as biomarkers for lower cardiotoxicity induced by EC-D neoadjuvant chemotherapy in BC patients.

ST Segment Elevation and Depressions in Supraventricular Tachycardia without Coronary Artery Disease

ST segment changes are well documented in literature during supraventricular tachycardias. We present a case of a 21-year-old male who presents with chest pain, shortness of breath, and dizziness with an ECG showing atrioventricular reentrant tachycardia and diffuse ST segment depressions. Patient spontaneously converted to sinus rhythm, but he was still complaining of crushing chest pain. ECG taken after conversion showed sinus rhythm at a rate of 65 and showed obvious persistence of ST depressions in majority of leads. Emergent left heart catheterization showed normal coronaries. Such ST depression is suggestive of global ischemia in small intracardiac vessels that cannot be evaluated by left heart catheterization.

Assessment of the Utility of Ordering a Troponin in Low- and Intermediate-Risk Patients Presenting to the Emergency Department with Supraventricular Tachycardia: A Retrospective Chart Review

BACKGROUND

A troponin assay is commonly sent for patients presenting to emergency departments (EDs) with supraventricular tachycardia (SVT). Multiple studies suggest that elevated troponin levels do not predict coronary artery disease in these patients. Patients with elevated troponins are more likely to have additional cardiac testing, which can lead to increased health care costs and unnecessary invasive procedures.

OBJECTIVE

Our objective was to evaluate low- to intermediate-risk patients (HEART [history, electrocardiography, age, risk factors and troponin] Score 1-6) presenting to the ED with SVT. Our hypothesis was that an elevated troponin would not predict major adverse cardiac events (MACE), but would be associated with increased hospital admission rates and lengths of stay.

METHODS

This was a retrospective cohort study of adult patients who presented with SVT to a large, urban, academic hospital ED over 4 years who had a troponin result. A total of 46 patients were included in the study.

RESULTS

Patients with a positive troponin (>0.05 ng/mL) had a hospital admission rate of 86% versus 21% for patients with negative troponin (p = 0.006); rate of cardiology consult of 86% versus 21% (p < 0.001); and a mean total length of stay of 4157 min versus 1347 min (p = 0.04). At 3 months, none of the patients with a positive troponin had an MACE, death from any cause, or positive results of cardiac testing.

CONCLUSIONS

Patients with a positive troponin result had significantly more admissions, cardiology consults, and longer hospital stays. These patients did not have an increased prevalence of MACE.

Review article: The utility of troponin and other investigations in patients presenting to the emergency department with supraventricular tachycardia

Patients with supraventricular tachycardia commonly present to the ED. There is a lack of consensus regarding assessment of these patients. Our aim was to determine the utility of troponin and four other investigations (full blood examination, electrolyte levels, thyroid function tests and chest X-rays) commonly requested for these patients. MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials (January 1992-March 2017) were searched for randomised controlled trials and observational studies (of sample size greater than 10). Our search strategy yielded no randomised controlled trials and seven observational studies with significant statistical heterogeneity among selected studies (I² 87.3%, P < 0.001). Included studies investigated a total of 1155 patients. All studies reported on the utility of troponin testing in this patient population. The pooled proportion of patients investigated with troponin was 0.66 (95% confidence interval 0.44-0.88). The pooled proportion of positive troponin tests was 0.32 (95% confidence interval 0.23-0.41). Only one study reported on the utility of the remaining four investigations with abnormal results as follows: thyroid stimulating hormone 14%, haemoglobin 6%, white cell count 19% and chest X-ray 22%. Investigations are commonly requested for patients presenting with supraventricular tachycardia. Troponin testing is commonly performed with a high proportion of positive findings although these results did not appear to be associated with major adverse cardiac events. Heterogeneity among studies and low levels of evidence precluded conclusions on full blood examinations, electrolyte levels, thyroid testing and utility of chest X-rays in this patient population.

Usefulness of laboratory and radiological investigations in the management of supraventricular tachycardia

OBJECTIVE

Although ED patients presenting with supraventricular tachycardia (SVT) are commonly investigated, the value of these investigations has been questioned. We aimed to determine the frequency and utility of investigations in patients with SVT.

METHODS

We undertook an explicit retrospective medical record audit of patients with SVT who presented to a single ED (January 2004 to June 2014). Data on demographics, presenting complaints, investigations and outcomes were extracted. The outcomes were nature and utility of investigations.

RESULTS

A total of 633 patients were enrolled (mean [SD] age 55.4 [17.7] years, 62% female). Laboratory investigations were common: electrolytes (83.7% of patients), full blood count (81.2%), magnesium (57.5%), calcium (39.3%) and thyroid function (30.3%). These investigations revealed many mildly abnormal results but resulted in electrolyte supplementation in only 19 patients: eight with mild hypokalaemia (potassium 3.0-3.5 mmol/L) and 11 with mild hypomagnesia (magnesium 0.49-1.1 mmol/L). Troponin was ordered for 302 (47.7%) patients, many of whom had no history or risk factors for cardiac disease, or ischaemic symptoms associated with their SVT. The troponin was normal, mildly and moderately elevated in 65.2, 24.5 and 10.2% of cases, respectively. Only seven (1.1%) patients were diagnosed with acute myocardial ischemia. Although 190 (30.0%) patients had a chest X-ray (CXR), it was normal in 78.4% of cases. All CXR abnormalities were incidental and not relevant to the immediate ED management.

CONCLUSION

Patients with uncomplicated SVT are over-investigated. Guidelines for ED SVT investigation are recommended. Further research is recommended to determine the indications for each investigation in the setting of SVT.

Symptoms in supraventricular tachycardia: Is it simply a manifestation of increased heart rate?

A significant proportion of patients in clinical practice may not have ECG recordings of the index tachycardia (non-documented SVT), or only have recordings of limited diagnostic value. Despite the highly specified symptomatic and ECG diagnostic criteria, diagnosis and referral for ablation treatment is not always straightforward. Although ECG based diagnostic or treatment algorithms have been well defined in literature, we need a symptom based diagnostic algorithm or scoring system in patients with suspected supraventricular arrhythmia. Individual approaches with a high suspicion index and concerning the paroxysmal nature and post attack symptoms would help us to identify patients suffering from SVT in complex cases.

Characterization of Cardiac Troponin Elevation in the Setting of Pediatric Supraventricular Tachycardia

Cardiac troponin (cTn) is currently considered the gold standard biomarker for detection of myocardial necrosis. Patients with supraventricular tachycardia (SVT) often present with symptoms resulting in cTn assessment; however, there are no data on the results of such testing in childhood. We hypothesized that cTn elevation would be common in the pediatric SVT population and would portend a benign prognosis. A retrospective review of all pediatric patients (≤21 years) presenting with SVT was performed. Clinical and electrocardiographic variables from the emergency department (ED) presentation were reviewed and clinical outcomes during subsequent follow-up assessed. Of 128 patients seen in the ED for SVT, cTn was assessed in 48 (38 %). Of patients with cTn assessment, 14 (29 %) patients demonstrated cTn elevation. Univariate predictors of cTn elevation included presentation with respiratory or gastrointestinal symptoms (50 vs 12 % and 42 vs 9 %; p = 0.008 and p = 0.01, respectively), lower mean arterial blood pressure (73 vs 85 mm Hg, p = 0.009), higher age-adjusted tachycardia rate (z score 9.3 vs 7.2, p < 0.001), and longer tachycardia duration (4.2 vs 1.0 h, p = 0.02). Multivariate logistic regression confirmed the association of age-adjusted tachycardia rate (odds ratio [OR] 3.8 per heart rate z score, confidence interval [CI] 1.9-11.8, p = 0.003) and duration (OR 1.5 per hour, CI 1.1-2.5, p = 0.03). Clinical outcome was excellent with no adverse sequelae during a median of 2.9 years of follow-up. Cardiac Tn elevation is common in the pediatric population presenting with SVT. Episode severity, characterized by respiratory or gastrointestinal symptoms, lower mean blood pressure, and increased tachycardia rate and duration are predictive. Clinical follow-up is favorable.

Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia

BACKGROUND

People with the cardiac arrhythmia supraventricular tachycardia (SVT) frequently present to clinicians in the prehospital and emergency medicine settings. Restoring sinus rhythm by terminating the SVT involves increasing the refractoriness of atrioventricular nodal tissue within the myocardium by means of vagal manoeuvres, pharmacological agents, or electrical cardioversion. A commonly used first-line technique to restore the normal sinus rhythm (reversion) is the Valsalva Manoeuvre (VM). This is a non-invasive means of increasing myocardial refractoriness by increasing intrathoracic pressure for a brief period, thus stimulating baroreceptor activity in the aortic arch and carotid bodies, resulting in increased parasympathetic (vagus nerve) tone.

OBJECTIVES

To assess the evidence of effectiveness of the VM in terminating SVT.

SEARCH METHODS

We updated the electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 7); MEDLINE Ovid (1946 to August week 3, 2014); EMBASE Classic and EMBASE Ovid (1947 to 27 August 2014); Web of Science (1970 to 27 August 2014); and BIOSIS Previews (1969 to 22 August 2014). We also checked trials registries, the Index to Theses, and the bibliographies of all relevant publications identified by these strategies.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that examined the effectiveness of VM in terminating SVT.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data using a standardised form. We assessed each trial for internal validity, resolving any differences by discussion. We then extracted and entered data into Review Manager 5.

MAIN RESULTS

In this update, we did not identify any new RCT studies for inclusion. We identified two RCT studies as ongoing that we are likely to include in future updates. Accordingly, our results are unchanged and include three RCTs with a total of 316 participants. All three studies compared the effectiveness of VM in reverting SVT with that of other vagal manoeuvres in a cross-over design. Two studies induced SVT within a controlled laboratory environment. Participants had ceased all medications prior to engaging in these studies. The third study reported on people presenting to a hospital emergency department with an episode of SVT. These participants were not controlled for medications or other factors prior to intervention.The two laboratory studies demonstrated reversion rates of 45.9% and 54.3%, whilst the clinical study demonstrated reversion success of 19.4%. This discrepancy may be due to methodological differences between studies, the effect of induced SVT versus spontaneous episodic SVT, and participant factors such as medications and comorbidities. We were unable to assess any of these factors, or adverse effects, further, since they were either not described in enough detail or not reported at all.Statistical pooling was not possible due to heterogeneity between the included studies.

AUTHORS' CONCLUSIONS

We did not find sufficient evidence to support or refute the effectiveness of VM for termination of SVT. Further research is needed, and this research should include a standardised approach to performance technique and methodology.

Cardiac troponin I elevation with supraventricular tachycardia: two case reports and review of the literature

Background

Although cardiac troponin I gives excellent accuracy in the identification of myocardial necrosis, it can also be elevated in a series of diseases other than acute coronary syndromes.

Case presentation

We present two cases of Chinese patients with a high serum troponin I level after an acute episode of paroxysmal supraventricular tachycardia with normal coronary arteries via angiography.

Conclusion

Abnormal troponin elevations can be seen in patients presenting with paroxysmal supraventricular tachycardia and angiographically-normal coronary arteries. Caution is advised with the use of invasive assessments such as coronary angiography in the differential diagnosis of patients with paroxysmal supraventricular tachycardia and elevated troponin levels.

Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia

BACKGROUND

Patients with the cardiac arrhythmia supraventricular tachycardia (SVT) frequently present to clinicians in the prehospital and emergency medicine settings. Restoring sinus rhythm by terminating the SVT involves increasing the refractoriness of AV nodal tissue within the myocardium by means of vagal manoeuvres, pharmacological agents or electrical cardioversion. A commonly used first-line technique to restore the normal sinus rhythm (reversion) is the Valsalva Manoeuvre (VM). This is a non-invasive means of increasing myocardial refractoriness by increasing intrathoracic pressure for a brief period, thus stimulating baroreceptor activity in the aortic arch and carotid bodies, resulting in increased parasympathetic (vagus nerve) tone.

OBJECTIVES

To assess the evidence of effectiveness of the Valsalva Manoeuvre in terminating supraventricular tachycardia.

SEARCH METHODS

We electronically searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 1 of 12, 2012); MEDLINE Ovid (1946 to January 2012); EMBASE Ovid (1947 to January 2012); Web of Science (1970 to 27 January 2012); and BIOSIS Previews (1969 to 27 January 2012). Trials registries, the Index to Theses and the bibliographies of all relevant publications identified by these strategies were also checked.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that examined the effectiveness of the Valsalva Manoeuvre in terminating SVT.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data using a standardised form. Each trial was assessed for internal validity with differences resolved by discussion. Data were then extracted and entered into Review Manager 5.1 (RevMan).

MAIN RESULTS

We identified three randomised controlled trials including 316 participants. All three studies compared the effectiveness of VM in reverting SVT with that of other vagal manoeuvres in a cross-over design. Two studies induced SVT within a controlled laboratory environment. Participants had ceased all medications prior to engaging in these studies. The third study reported on patients presenting to a hospital emergency department with an episode of SVT. These patients were not controlled for medications or other factors prior to intervention.The two laboratory studies demonstrated reversion rates of 45.9% and 54.3%, whilst the clinical study demonstrated reversion success of 19.4%. This discrepancy may be due to methodological differences between studies, the effect of induced SVT versus spontaneous episodic SVT, and participant factors such as medications and comorbidities. We were unable to assess any of these factors further, nor adverse effects, since they were either not described in enough detail or not reported at all.Statistical pooling was not possible due to heterogeneity between the included studies.

AUTHORS' CONCLUSIONS

We did not find sufficient evidence to support or refute the effectiveness of the Valsalva Manoeuvre for termination of SVT. Further research is needed and this should include a standardised approach to performance technique and methodology.