Evaluation of Aortic Prosthetic Valves. JASE 2018. PPT.
Prosthetic Heart Valves
Tag: TTE
Mitral Valve analysis
New Concepts for Mitral Valve Imaging. Ann Cardiothorac Surg. 2013 Nov; 2(6): 787–795.
Method—Comparison of Transthoracic and Transesophageal Echocardiography. Clin. Cardiol. 25, 517–524 (2002)
Virtual TEE: spectral Mitral valve
Echocardiographic atlas of the mitral regurgitation. J Saudi Heart Assoc. 2011 Jul; 23(3): 163–170.
Prediction of the annuloplasty ring size in patients undergoing mitral valve repair using real-time three-dimensional transoesophageal echocardiography. Eur J Echocardiogr. 2011 Jun; 12(6): 445–453.
Mitral Annular Evaluation With CT in the Context of Transcatheter Mitral Valve Replacement. JACC: CARDIOVASCULAR IMAGING, VOL. 8, NO. 5, 2015.
MAY 2015:612–5.
Cardiac anesthesiologists and LVAD patients: Pro vs Cons
There’s been a big debate re: who should care for LVAD patients… a general anesthesiologist or a cardiac anesthesiologist? See below for pros and cons of each. Ultimately, I think all anesthesiologists should be comfortable caring for these patients as we’ll see more and more LVAD patients undergoing procedures.
Troubleshooting the Left Ventricular Assist Device. Emergency Medicine. 2016 February;48(2):58-63.
LVAD Parameter Abnormalities:
- High power, low-pulsatility index and fluctuating pump speed: Consider pump thrombosis or hypotension, vasodilation, initial response to exercise.
- High power with high pulsatility index: Consider fluid overload, normal physiological response to increased demand; myocardial recovery.
- Low power, low pulsatility index, and unchanging speed: Consider hypertension or inflow/outflow obstruction, LV failure, dysrhythmia.
- Low power with normal or high pulsatility index: Consider suction event.
Ventricular assist devices and non-cardiac surgery. BMC Anesthesiology201515:185
- Goals of care for LVAD patients undergoing non-cardiac surgery should be directed at maintaining forward flow and adequate perfusion. Three main factors that affect LVAD flow are preload, RV function, and afterload.
- The right ventricle is the primary means of LVAD filling; therefore, maintaining RV function is imperative.
- Marked increases in systemic vascular resistance should be avoided.
- Generally, decreases in pump flow should first be treated with a fluid challenge. Hypovolemia should be avoided and intraoperative losses should be replaced aggressively. Second line treatment should include inotropic support for the right ventricle.
- Low-dose vasopressin (<2.4 U/h) may be the vasopressor of choice due to its minimal effect on pulmonary vascular resistance.
- Standard Advanced Cardiovascular Life Support Guidelines should be followed; however, external chest compressions should be avoided during cardiac arrest.
- Steep Trendelenburg may increase venous return, risking RV strain. Peritoneal insufflation for laparoscopic surgery also increases afterload and has detrimental effects on preload. Insufflation should utilize minimum pressures and be increased in a gradual, step-wise fashion.
- TEE can be extremely valuable in diagnosing the cause of obstruction.
LVAD: What Should I report? Feb 2017 ASE conference. **ECHO**
- Higher the RPMs (pump speed)
- More LV compression, smaller LV size
- Less functional MR
- More AI, less AV opening
- Less LVED diameter
- De Novo Aortic Regurgitation Post LVAD
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Proposed mechanisms
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Aortic valve remains closed during systole
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Commissural fusion of the aortic valve from disuse
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Subsequent degeneration of valve
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Turbulent blood backflow from small outflow cannula onto a closed valve
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Persistent elevation of aortic root pressure –> aortic root dilation and valve incompetence
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Treatment
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Lower LVAD speed (but that may worsen mitral regurgitation)
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Aortic valve surgery or percutaneous intervention
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Heart transplant
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- RV Fractional Area Change (RV FAC)
- RVFAC is a rough measure of RV systolic function (4 chamber view)
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RVFAC = (RVEDA – RVESA) / RVEDA
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Normal RVFAC = 35 – 63%
Ventricular Assist Device (VAD). LifeInTheFastLane.com. .
Care of the LVAD patient PPT. Summit 2014.
- Pulsatility Index:
- normally decrease as pump speed is increased
LVAD: Understanding equipment and Alarms. Duke Heart Center PPT.
LVAD Management in the ICU. Crit Care Med 2014; 42:158–168.
My blog posts:
Transthoracic Echocardiography (TTE)
Transthoracic echo: a beginner’s guide #tte #cardiac #echo #meded
Knowing how to do a quick focused echo exam can be instrumental in diagnosis as well as treatment. This has helped me determine how severe cardiac tamponade has been in an emergent case prior to induction when there was no prior echo. There are so many more useful answers that a bedside echo can provide. Time to get acquainted.
Helpful links:
- Virtual Transthoracic Echo
- TeachingMedicine.com
- A beginner’s guide to learning basic echocardiography
- Echocardiographer.org
- E-echocardiography.com
- Echo of the Day
- Case of the Week
- Sample Echo search by category
Helpful articles:
- Focused Cardiac Ultrasound: Recommendations from the American Society of Echocardiography
- Philips Tutorial: Intro to TTE
- YouTube: Bedside Ultrasound Basic Cardiac
- YouTube: Standard TTE views
TAVR Team: conscious sedation vs. general anesthesia
Today, we had a guest speaker Christian Spies from Queen’s Hospital in Hawaii who spoke on his experience with his TAVR team and conscious sedation vs. general anesthesia for these patients. More specifically, we are speaking of the transfemoral route.
Keypoints:
- Patient selection is key (consider for COPD; bad for OSA)
- Short surgical time for monitored anesthesia care (MAC)
- Decrease invasive monitoring (no PA catheter,+/-CVP)
- No difference in hospital LOS or 1 year mortality rate
- Move from TEE to TTE if MAC
- Be prepared to convert MAC to GA (can be difficult in already tenuous patient in a crowded space under the drapes)
- MAC agents: dexmetetomidine, propofol, ofirimev
- Decrease pressor use
- Develop an algorithm for MAC vs. GA and patient selection
For my own lit search:
- Anaesthesia Nov 2011: Sedation vs general anaesthesia for the ‘high-risk’ patient – what can TAVI teach us?
- JACC May 2012: The Minimalist Approach for Transcatheter Aortic Valve Replacement in High-Risk Patients
- Cardiac Interventions Today May 2012: Rouen Experience Supports Safety of TAVR Using Local Anesthesia
- MedPage Today July 2012: TAVI: No Need for Patients to ‘Go Under’
- Amer J Card Jan 2013: Effect of Local Anesthetic Management With Conscious Sedation in Patients Undergoing Transcatheter Aortic Valve Implantation
- SCA 2013: PBL — Anesthesia for TAVR
- Indian Heart J March 2014: Transcatheter aortic valve implantation under conscious sedation – the first Indian experience
- TCTMD Mar 2015:As TAVR Evolves, Local Anesthesia Could Be an Option for Lower-Risk Patients
***Update May 1, 2018***
We at Scripps Memorial Hospital in La Jolla do most of our transfemoral TAVRs via conscious sedation assuming appropriate patient selection. These patients still tend to be the inoperable patients not cleared for open heart AVR (aortic valve replacement). My techniques and choices for setup have changed over time as I’ve had a chance to fine-tune my plan based on prior experiences with TAVR. Patients typically come to the hybrid room with a 20g PIV placed by the pre-op RN.
My Setup:
- 4 channel Alaris pump:
- dexmedetomidine @ 0.7 mcg/kg/hr until incision –> 0.4 mcg/kg/hr until valve deployment –> off
- norepinephrine @ 2 mcg/min (titrating on/off, up/down as vitals suggest)
- Isolyte (IV carrier fluid) @ 200ml/hr until valve deployment –> 50ml/hr
- Cordis neck line
- Initially, I would have the interventional cardiologist setup a femoral venous line since they’re getting access to the groin. However, the cardiologist would use that femoral line for emergent ECMO cannulation and I would lose my venous access and have to depend on a measly 20g PIV. Nowadays, I try for a short 14g or 16g PIV. If I can’t get one, the patient gets an awake right IJ cordis for large venous access.
- Hot line fluid warmer with blood-Y tubing: this is for hookup to a large PIV or cordis line
- Right radial arterial line
- I started only placing right radial arterial lines because there was a case of a dissection and I immediately lost my left radial arterial line and couldn’t do pressure monitoring. I insist on only using the RIGHT radial for my arterial monitoring. Do not let the cardiologist only give you arterial monitoring based on their femoral arterial access. It will only give you intermittent monitoring and there are critical points leading up to the deployment where you need CONTINUOUS arterial monitoring. Therefore, I’ve found the right RADIAL arterial line best for continuous monitoring.
- Facemask for continuous oxygen at 10L/mim with ETCO2 monitoring
- For trans-subclavian/axillary approach vs. transfemoral approach TAVR, I’ll put in a supraclavicular block right after Cordis/large-bore PIV venous access for patient comfort while still utilizing conscious sedation/MAC.
My Technique:
- When the patient gets to the room, transfer patient to OR table. Start IV fluids @ 200ml/hr. Cases that go well are about 2 hours from start to end.
- Facemask O2 at 10L/min.
- Start sedation: precedex/dexmedetomidine @ 0.7 mcg/kg/hr. Some patients may receive 1-2mg midazolam x 1 and 25-50mcg fentanyl for radial art line placement.
- Place right radial art line with lidocaine for skin numbing. Place PIV with lidocaine. If unable to get access for PIV, prep neck –> sterile gown/glove/drapes for U/S guided Cordis placement with lidocaine.
- OR staff preps patient. Antibiotics prior to incision.
- At incision –> precedex to 0.4 mcg/kg/hr. 25-50mcg fentanyl PRN discomfort. 10-20mg propofol push for discomfort if needed while large sheath placed for valve deployment.
- Crossing valve –> BP changes. Manage with volume or levophed.
- Valvuloplasty
- Don’t treat over-drive pacing too aggressively when the valve is deployed. Typically, once the new valve is in, a little volume will help normalize the BP.
- Once valve is deployed, turn precedex off. No other sedation or BP meds needed. Change IVF rate to 50ml/hr.
- Patient heads to PACU awake, interactive, and comfortable.
What techniques do you like to do? Any suggestions on a different approach?
Sleepy Time 