Thread by @KarlaAsturias

Physical exam in patients with heart failure is ✨essential✨

Did you know that you can assess the volume status of a heart failure patient using a blood pressure cuff and a stethoscope or doppler? 🤔

What is this sign called?

#CNshowmeasign

Valsalva maneuver assesses the blood pressure response during forced expiration. An abnormal response called “square-wave” can reflect states of ⬆️⬆️LV filling pressures.

To perform this maneuver:
☑️Inflate the BP cuff 10-15 mmHg above SBP
☑️Ask the patient to exhale or do abdominal straining against a closed airway
☑️Listen to Korotkoff sounds with a stethoscope or doppler throughout the phases

Initially, the strain from the maneuver will ⬆️SBP (+ Korotkoff sounds) but will also ⬆️intrathoracic pressure, leading to ⬇️venous return.

What happens next will help us differentiate our patient’s volume status🤩

☺️Euvolemic: ⬇️venous return will translate into ⬇️CO and SBP, so the initial Korotkoff sounds will go away

🤒Hypervolemic: ⬇️venous return will have little impact given vascular congestion, and Korotkoff sounds will remain present while the strain is sustained

The release of the strain will result in ⬇️SBP and the absence of Korotkoff sounds in both cases. In euvolemic patients, a delayed ⬆️SBP is expected -due to vasoconstriction and ⬆️venous return-

This can be summarized in 4 big phases:
1️⃣ Initiation: +Korotkoff sounds in both
2️⃣ Maintenance: +Korotkoff sounds in hypervolemia
3️⃣ Release: -Korotkoff sounds in both
4️⃣ Recovery: overshoot response in euvolemia

The shape that produces the sustained increased SBP during phase 2 in hypervolemic patients is the cause of its name “square-wave response”

A square-wave response to the Valsalva maneuver correlates to elevated PCWP with good sensitivity (~100%) and specificity (~90%) for PCWP > 15 mmHg. On a small cohort, NPV of this finding was described as 💯%.

Remember the limitations of this finding:
✏️ It can be challenging in patients with significant dyspnea
✏️ It can be inaccurate in patients with arrhythmias
✏️ Poor effort can result in equivocal results
✏️ Isolated ⬆️RV filling pressures will result in a negative test

The Valsalva maneuver was described more than 300 years ago, but it was until the 1940s and 1950s that the square wave pattern during the maneuver was formally described in patients with elevated filling pressures📝

Since then, it has represented a useful and noninvasive addition to bedside examination of volume status. 🫀🩺

#CNshowmeasign was brought to you by @patrickzakka and @a_h_ghoneem

A huge special 🙌🏼thank you🙌🏼 to @Tdonisan (for the amazing graphics), and @tdonisan, @amitgoyalmd, @a_h_ghoneem and @patrickzakka for reviewing!

Thank you to all the @Cardionerds for reading!✨

Take a look at these sources for more information!📚