The Three Clinical Stages

Figure 35-1 provides a model to quickly assess the probability of a WCT being VTach.

Figure 35-1 Quick assessment to approximate the probability of a WCT being VTach.

© Jones & Bartlett Learning.

Description

Taking the concept of a WCT of unknown origin a bit further, let’s try to come up with a simplified approach that can easily guide our clinical decision-making process. We know that VTach is the most common lethal arrhythmia. We know that 80% of WCTs of unknown origin are VTachs.^1-5 In addition, in Chapter 36, Wide-Complex Tachycardia: Criteria, we will see that most of the criteria focus almost entirely on diagnosing VTach rather than SVTs-A. Finally, we know that VTach has to be our primary clinical concern, since it is more commonly associated with life-threatening hemodynamic instability. Get the picture? We primarily need to focus on diagnosing VTach.

Likewise, when we think about clinical management of these rhythms as a group (WCTs), we need to focus primarily on the management and control of VTach, while extending the safety profile to cover both. We cannot, however, overlook the specific treatments available for the individual rhythms, since we are not dealing with any benign rhythms. Lucky for us, the 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients with Supraventricular Tachycardia⁶ and the 2017 AHA/ACC/HRS Guideline for Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death⁷ have provided a treatment strategy that casts a wide safety net encompassing the treatment of all the WCTs under one unified, safe approach regardless of the identity of the WCT of unknown origin. As we shall see, this becomes extremely important during the emergent period when the patient is at a very high risk of injury or death, and time becomes an even rarer commodity.

Now that we have taken a look at the problems we face, let’s start formulating a specific approach to the diagnosis and treatment of WCTs using some simple medical concepts. Clinically, patients present in one of three different clinical stages: emergent, urgent, and nonurgent (Figure 35-2). Let’s take a look at what each one means:

Figure 35-2 Three clinical stages of patient presentation to clinicians: emergent, urgent, and nonurgent.

© Jones & Bartlett Learning.

1. Emergent stage: Things that will kill the patient. Emergent refers to a life-threatening state where immediate attention to diagnosis, treatment, and stabilization should not be delayed. Severely hemodynamically unstable patients and unresponsive patients fit within this category.
2. Urgent stage: Things that will hurt the patient. Urgent refers to those patients who present with life-threatening or limb-threatening clinical states where the need for attention and treatment is necessary as quickly as possible, but you are provided a small amount of “wiggle-room” to analyze the situation in greater depth before deciding on the clinical course. Patients with initial presentations showing a functional but decreased or decreasing level of hemodynamic instability fall under this category.
3. Nonurgent stage: Everything else! Nonurgent refers to patients who do not require immediate attention and are hemodynamically stable, allowing the patient to be evaluated in a timely (but still as rapid as possible) manner prior to instituting a course of action.

Author’s Disclaimer: For completeness, we’d like to clarify that the clinical approach to the acute and nonurgent stages is our own individual approach and is not part of a protocol, has not undergone clinical trials, and is not part of a generally accepted consensus (if there ever has been such a thing). It has been organized after reviewing the literature and has been formulated through years and years of experience. We encourage you to approach our ideas in the same way that you should approach all clinical information in the first place: Figure out what makes sense and works for you, then incorporate that into your practice. Then, discard the rest.

Our approach to patients with WCTs requires us to narrow our focus down a bit further into just two groups: emergent and nonurgent. (For the sake of simplicity, we will combine the emergent and urgent stages.) The main priority of this chapter is to provide you a framework to follow as you focus on making the best “educated guess” of the rhythm while maximizing the clinical safety net for your patient.

We will start by making you comfortable with the decision-making process of the typically hectic emergent period. Then in Chapter 36, Wide-Complex Tachycardia: Criteria, we will discuss the nonurgent phase and examine the tools and criteria that are typically used to arrive at a more definitive diagnosis. However, instead of just listing the findings and criteria as most books and websites tend to do, we will try to provide you with a functional understanding of the principles involved. The reality is that these findings are so extensive that unless you use them every day, you will quickly forget them unless you have an IQ score of 170+ and a photographic memory. Our goal is to guide you through this confusing minefield as easily, efficiently, and safely as possible.