Thread by @dritsyk

MAPSE in #IntensiveCare (with examples)🧵#FOAMcc #FOAMed #MedTwitter #Hemodynamic #POCUS #EchoFirst #CriticalCare
Take homes:
1⃣ Redefining "the hyperdynamic heart" with #MAPSE
2⃣ MAPSE is better than EF in the #ICU
3⃣ Linking MAPSE with supply/demand-ischemia
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1⃣ Can MAPSE redefine "the hyperdynamic heart?
The term "hyperdynamic LV" - EF > 55% - is misleading. It has no relation to a hyperdyanmic circulation; SV/CO. Someone bleeding to death has a hyperdynamic heart, but the circulation is life-threatening hypodynamic.
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MAPSE is cardiac motion, and defining the hyperDYNAMIC heart as good cardiac motion makes perfect sense. Recent geometrical analysis of cardiac pumping shows that MAPSE is the main determinant of SV. Fig from @mugander: tinyurl.com/mxbfmcyk
Why?
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To save energy by not moving the lungs in diastole, total intra-PERICARDIAL volume is constant during pumping. The main pumping mechanism is therefore MAPSE. Also, reproduced using TTE.
Fig. @strain_rate:
tinyurl.com/mapse
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Example1⃣: #TEE #EchoFirst Visually high EF, but...
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Example1⃣: #TEE #EchoFirst Visually high EF, but..
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...MAPSE is low (lateral 7 cm, septal 6 cm), reflecting reduced LV motion and a HYPOdynamic heart. The circulation is also hypodynamic: Low stroke volume (52 mL, VTI 15.9cm) and hypoperfusion (oliguria, low ScvO2, high PvaCO2).
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2⃣Why is MAPSE better than EF in #IntensiveCare?
The intensive care - #mechanicalventilation, anesthesia, SIRS - decreases preload. ⬇️Preload and ⬇️EDV causes ⬇️SV and ⬇️MAPSE. Ref: tinyurl.com/2trt34cr
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MAPSE uniformly falls with conditions that reduced LV function. The EF is, however, unchanged, because SV and EDV falls and EF = SV/EDV - leaving it unchanged.
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Example2⃣: Same patient as above. Biplane Simpsons gives us a high EF (59%), low preload (low LVEDV, PPV > 15 on art line). MAPSE is low (lateral 7mm, septal 6mm).
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In addition, with TTE #EchoFirst, MAPSE is much easier than EF, especially in when image quality is poor. Finally, MAPSE is a quantitative and is more objective than visual EF.
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3⃣Can MAPSE reveal supply/demand-ischemia and type 2 MI?
The longitidunal fibres responsible for MAPSE are also subendocardial and the most vulnerable for supply/demand-ischemia. Type 2 MI has otherwise unpredictable clinical features from ECG, symptoms and echo.
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Impaired longitudinal function is seen in ischemic heart disease and troponin release, even without regional wall motion abnormalities.
Ref: tinyurl.com/4vm4an9b
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⬇️MAPSE in ICU correlates with ⬆️troponin.
Ref: tinyurl.com/bp75ctzj
(btw, in this study, EF did not)
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Conclusion:
#MAPSE is valuable in #CriticalCare. 1⃣It can improve our understanding in cardiac function; 2⃣ It's easier to perform, easier to interpret; and 3⃣ It can possibly warn about supply/demand-ischemia.
...end 🧵
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*MAPSE is low (lateral 7 mm, septal 6 mm)

@LBergenzaun