Clinical differentiation of narrow QRS complex tachycardias

Association of Paroxysmal Supraventricular Tachycardia with Ischemic Stroke: A National Case-Control Study

BACKGROUND AND PURPOSE

Cardioembolic stroke accounts for approximately 15%-20% of all ischemic strokes. Atrial fibrillation constitutes one-half to two-thirds of all cardioembolic stroke events. The association of paroxysmal supraventricular tachycardia (PSVT) with ischemic stroke remains unclear. A national case-control study was conducted to identify the risk factors, including PSVT, for ischemic stroke in Taiwan.

METHODS

We designed a national case-control study comprising patients diagnosed with ischemic stroke (n = 5633) from 1997 to 2011; each patient from the case group was randomly matched with the control group (n = 30,895) in Taiwan. Data were retrospectively collected from Taiwan's National Health Insurance Research Database, which contains not only claims data on hospitalization, emergency room visits, and outpatient department visits, but also patient characteristics.

RESULTS

Logistic regression analysis was used to identify the risk factors for ischemic stroke. Independent risk factors for ischemic stroke included age (in 5-year intervals; odds ratio [OR], 1.76; 95% confidence interval [CI], 173-1.78), the male sex (versus the female sex; OR, 1.88; 95% CI, 1.74-2.01), chronic kidney disease (OR, 3.09; 95% CI, 2.67-3.57), PSVT (OR, 2.05; 95% CI, 1.30-3.19), and aspirin use (OR, .04; 95% CI, .03-0.05).

CONCLUSIONS

Our study is the first in Taiwan to identify PSVT as a significant risk factor for ischemic stroke. New antithrombotic regimens, including aspirin, can be recommended for the primary prevention of stroke and for reducing the burden of stroke for patients with PSVT.

Trauma Associated With Cardiac Dysrhythmias: Results From a Large Matched Case-Control Study

BACKGROUND

Various cardiac dysrhythmias such as supraventricular and ventricular premature beats, supraventricular and ventricular paroxysmal tachycardia, atrial and ventricular fibrillation and atrial flutter have been reported in case series, as complications of blunt cardiac and thoracic trauma. The objective of this research was to determine whether thoracic or blunt cardiac injury is associated with cardiac dysrhythmia in a large multistate hospitalized population.

METHODS

Cases and matched (by age) controls were identified based on hospital discharge information that was collected from 986 acute general hospitals across 33 states in 2001. Both the exposure (thoracic trauma and blunt cardiac injury) and the outcome (cardiac dysrhythmias) were identified based on ICD-9-CM discharge diagnoses. Unadjusted and conditional adjusted (for gender, race, length of stay, and primary source of payment) multivariate logistic regression analyses were performed.

RESULTS

After adjusting for potential confounders, patients 50 years and younger diagnosed with blunt cardiac injury had a fourfold (95% confidence interval, 1.40-11.60) increase in the risk of cardiac dysrhythmia. Independent of potential confounding factors, discharge for blunt cardiac injury among patients 51 to 70 years old was associated with a twofold (95% confidence interval, 1.36-3.82) increased risk for cardiac dysrhythmia.

CONCLUSION

Blunt cardiac injury was found to be a significant risk factor for cardiac dysrhythmia. Longitudinal studies are needed to better establish the association between trauma and cardiac dysrhythmias.

Wolff Parkinson White (WPW) syndrome: what the critical care nurse needs to consider when administering antiarrhythmics

This paper discusses the importance of critical care and emergency nurses having an understanding of why pre-existing cardiac disorders can influence antiarrhythmic treatment. The patient with a pre-excitation syndrome is usually managed in a coronary care unit. However, these patients may be admitted to an intensive care unit (ICU) with complications of Wolff Parkinson White (WPW) syndrome; for example post cardiopulmonary arrest or WPW as a co-morbidity. It is common practice in critical care areas for registered nurses to administer antiarrhythmics without a doctor's prescription in life-threatening situations. Therefore, the critical care nurse must have knowledge of the implications of administering standard antiarrhythmic agents if this patient reverts into a tachyarrhythmia. If antiarrhythmics are administered that are contraindicated in patients with WPW syndrome, then there is potential for deleterious effects. This case study highlights the different pharmacological agents for treating tachyarrhythmias in a patient with WPW syndrome. The paper outlines the correct treatment and discusses the deleterious effects of incorrect administration of drugs in WPW syndrome.

Atrial arrhythmias

Atrial arrhythmias are commonly encountered by the primary care clinician. They are usually asymptomatic or have only minor symptoms, unless the ventricular rate becomes very rapid. The challenges for the clinician are to recognize the benign from the more severe arrhythmias, to identify and treat the precipitating cause, to control the symptoms that concern the patient, and to prevent any complications. There are new medicinal and nonmedicinal treatments available that offer greater likelihood of acute and long-term success in the treatment, and sometimes cure, of the original arrhythmias.