Supraventricular Tachydysrhythmias Cost-Effective Tips

1. Minimize unnecessary laboratory testing in young, healthy patients who quickly respond to treatment. While hyperthyroidism, electrolyte abnormalities, anemia, and drug/alcohol use have all been associated with SVT, it is unlikely that all of these etiologies need to be investigated in every single patient. A focused history and physical examination will help guide which, if any, laboratory testing is appropriate. Additionally, if a patient discloses that he/she abuses drugs or alcohol, a confirmatory test is likely unnecessary. 

2. Avoid routinely sending cardiac enzymes and avoid admitting patients with SVT for acute coronary syndrome (ACS) evaluation. While certain forms of SVT (e.g., NPJT) may be associated with ACS/MI, most patients with SVT do not require evaluation for cardiac ischemia. In fact, ordering cardiac enzymes in all patients with SVT can be a dangerous approach that leads to unnecessary antianginal therapy and invasive testing. Several studies have shown that markers of cardiac ischemia (troponin I) can be elevated, but that patients do not have significant coronary artery disease on further evaluation. Of course, in patients in whom you suspect cardiac ischemia or who have significant risk factors, appropriate evaluation is indicated and may include serial cardiac enzymes and admission.  

3. Give the patient a copy of their ECG documenting a prior SVT or evidence of ventricular preexcitation and ask them to carry it at all times. An ECG contains valuable information that may be useful when the patient presents for follow-up, returns to your ED with recurrent symptoms, or visits an outside hospital where the providers don’t have immediate access to prior ECGs. It is a simple, inexpensive intervention but may result in more efficient and appropriate treatment and a decrease in unnecessary testing/work-up.

Purchase the individual issue for 2 more cost effective tips

Supraventricular Tachydysrhythmias Risk Management Pitfalls

1. “I have a lot of experience differentiating SVT with aberrancy from VT – I’m really on top of the various criteria you can use to tell one from the other.” That’s great! Until the 54-year-old male who you were “sure” had SVT drops his blood pressure to 50/30 after you give him diltiazem and requires aggressive resuscitation and ICU admission. There are no criteria that are fool proof in differentiating SVT with aberrancy from VT. When the diagnosis is not 100% known to be SVT, a wide complex arrhythmia must be treated as VT. Medications used to treat SVT (diltiazem, verapamil) can be lethal in a patient with VT. 

2. “I can’t believe that patient submitted a complaint. Adenosine was the indicated treatment for his SVT and I administered it right after he rolled in the door.” It’s true that adenosine was an appropriate treatment, but patients appreciate forewarning of the side effects of medications. It is good practice to initiate treatment promptly, but take a minute to include patients in the overall plan and prepare them before administering medications that cause a sense of impending doom or death. 

3. “That lady had “psych” written all over her – a history of depression, anxiety, and frequent ED visits for palpitations.” Palpitations should not routinely be attributed to anxiety. Often, an ECG and telemetry monitoring in the ED will not document a dysrhythmia but Holter monitoring or event recorders might. It has been well documented that many patients, especially females, with SVT are initially misdiagnosed with anxiety. Referring these patients for additional testing may ultimately lead to a diagnosis, treatment that controls symptoms, and fewer visits to the ED. 

4. “Young people can tolerate rapid heart rates; I never use electrical cardioversion because those young whipper-snappers never seem unstable – a blood pressure of 95/50 is normal for them.” While younger patients may be better able to tolerate rapid ventricular response in SVT, there is still potential for precipitous deterioration. Atrial fibrillation in WPW syndrome is an inherently unstable rhythm where heart rates may be 300 bpm and the potential for deterioration to ventricular fibrillation is real. If there is a history of WPW syndrome or ECG findings consistent with WPW syndrome and atrial fibrillation, do not hesitate to cardiovert if there is any hint of hemodynamic instability. 

5. “The elderly gentleman with a history of myocardial infarction (MI) had shortness of breath and an irregular rhythm on ECG with a rate of 120. I knew he wouldn’t tolerate a heart rate of 120 for very long so I administered metoprolol for rate control.” Unfortunately, that patient had a history of severe COPD in addition to coronary artery disease; the ECG showed MAT (not atrial fibrillation) and the patient had profound bronchospasm in response to treatment with a β-blocker. In both MAT and NPJT, the best course of action is to treat the underlying precipitant of the SVT rather than the heart rate and to avoid medications that are relatively contraindicated. In this case, treatment of the underlying COPD may have relieved the patient’s symptoms of shortness of breath and terminated or slowed the MAT.

Purchase the individual issue for 5 more Risk Management Pitfalls, plus treatment recommendations, evidence-based guidelines, and more

Supraventricular Tachydysrhythmias Case Study

Case Study:

A 35-year-old female suddenly develops palpitations and chest discomfort while white-water rafting. Paramedics arrive and record a HR of 190 bpm.  She is immediately transported to the local emergency department where you are working.  On exam she appears anxious and has a regular HR at a rate of 75 bpm.  An ECG, basic labs, and a urine toxicologic screen are ordered.  An hour later the toxicologic screen and basic labs come back negative.  You are about to discharge her with a diagnosis of acute anxiety attack when you realize that you haven’t seen her ECG yet…

Soon after, you see paramedics rolling a gurney with an older male into another room. They give you the quick report that the patient is having intermittent shortness of breath and chest discomfort.  You look at the vital signs on the run sheet and are reassured to see that his blood pressure is 140/80 with an O₂ sat of 98% on room air.  You ask the nurse to place the patient on a monitor while you take care of a few other things.  Minutes later, you are paged overhead to his room and the nurse tells you, “His heart rate is 180/min and he really doesn’t look good.”  The patient is diaphoretic and his BP is now 100/50.  You ask the patient how he is feeling and he mumbles a response that is barely comprehensible.  The monitor shows a narrow complex tachycardia.  An ECG is obtained and no P waves are discernible.  You’re on the fence; can you convert this SVT with adenosine or should you cardiovert?

Conclusion of the above case study…

You prepared the discharge paperwork for the anxious 35-year-old female and asked the nurse to send her home with primary care physician follow-up. The patient was walking towards the exit when the nurse handed you the ECG you requested for this patient. The ECG demonstrated what you had expected: sinus rhythm. However,the QRS complex caught your eye and you noted a delta wave. Luckily, the patient hadn’t left the ED yet. After an informed discussion with the patient regarding her new diagnosis of WPW syndrome, she was discharged home with a follow-up cardiology appointment within the next week and instructions to follow-up with an electrophysiologic specialist.  

You used synchronized cardioversion to treat the SVT in the older male presenting with intermittent chest pain and shortness of breath. You thought about using adenosine, but his declining mental status was concerning enough to classify his SVT as unstable. He converted to sinus rhythm with a rate of 90 bpm. Looking back at his records from prior visits, you realized his blood pressure had always been around 170/90. It seems very clear now that his blood pressure of 100/50 today was producing mental status changes and you were glad that you made the call to cardiovert rather than use adenosine.

Purchase the individual issue today