Cardiac resynchronization therapy is 3.3 X less likely to help if low Vitamin D – July 2024

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Vitamin D as a predictor of clinical response among patients with cardiac resynchronization therapy (CRT)

Phuuwadith Wattanachayakul MD1,2, | Thitiphan Srikulmontri MD1,2 , Vitchapong Prasitsumrit MD3, Thanathip Suenghataiphorn MD4,
Pojsakorn Danpanichkul MD5, Natchaya Polpichai MD6, Sakditad Saowapa MD5 | Abiodun Idowu MD1,2 | Aman Amanullah MD2,7

Introduction: Cardiovascular and noncardiovascular comorbidities have been recog­nized as predictors of clinical response in patients receiving cardiac resynchroniza­tion therapy (CRT). However, data on vitamin D as a predictor of CRT response are conflicting.

Method: We identified studies from MEDLINE and Embase databases, searching from inception to May 2024, to investigate the association between 25-OH vitamin D lev­els before CRT implantation and outcomes. Studies had to report 25-OH vitamin D levels or the proportion of patients with vitamin D insufficiency and categorize out­comes as CRT responders or nonresponders. We extracted mean 25-OH vitamin D and standard deviations for both groups from each study and calculated the pooled mean difference (MD). We also retrieved risk ratios, and 95% confidence intervals (CIs) for the association between vitamin D insufficiency and lack of CRT response, combining them using the generic inverse variance method.

Results: Our meta-analysis included four studies. CRT responders had higher levels of 25-OH vitamin D than nonresponders, with a pooled MD of 8.04ng/mL (95% CI: 3.16-12.93; i2=48%, p<.001). Patients with vitamin D insufficiency before implanta­tion had higher odds of lacking response to CRT, with a pooled RR of 3.28 (95% CI: 1.43-7.50; I2 = 0%, p = .005) compared to those with normal vitamin D.

Conclusions: CRT responders had higher 25-OH vitamin D levels compared to non­responders. Vitamin D insufficiency was associated with a higher risk of nonresponse to CRT. These findings highlight the importance of monitoring and managing vitamin D levels in these patients.
 Download the PDF from VitaminDWiki

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VitaminDWiki – Cardiovascular category:

530 items In Cardiovascular category

Cardiovascular category is associated with other categories: Diabetes 31, Omega-3 31 , Vitamin K 25 , Intervention 22 . Mortality 20 , Skin - Dark 18 , Magnesium 17 , Calcium 14 , Hypertension 14 , Trauma and surgery 13 , Stroke 13 , Kidney 12 , Metabolic Syndrome 11 , Seniors 10 , Pregnancy 8 as of Aug 2022

• Overview Cardiovascular and vitamin D
• Cardiovascular Disease is treated by Vitamin D - many studies 39+ meta-analyses
• Coronary Artery Disease and Vitamin D - many studies 18+
• Cardiovascular problems reduced by Omega-3 - many studies 34+
• Arteries and Atherosclerosis and Vitamin D - many studies 71+
• Atrial Fibrillation decreased by Vitamin D or Magnesium - many studies 26+
• Statins and Vitamin D - many studies 25+
• Arterial Stiffness and Vitamins – only Vitamin D was found to help – meta-analysis Feb 2022
• Those raising Vitamin D above 30 ng were 1.4 X less likely to die of Heart Attack (VA 19 years) – Oct 2021
• Giving free vitamin D to every Iranian would pay for itself by just reducing CVD – Oct 2021
• Sudden Cardiac Arrest – 2.8 X higher risk if low vitamin D – 2019
• Peripheral arterial disease risk is 1.5X higher if low vitamin D – meta-analysis March 2018
• Heart attack ICU costs cut in half by Vitamin D – Oct 2018
• Cardiovascular disease 2.3 X more-likely if poor Vitamin D Receptor – Aug 2022

Cholesterol, Statins

• Cholesterol is needed to produce both Vitamin D and Cortisol
• Overview Cholesterol and vitamin D
• Statins and Vitamin D - many studies statins often reduce levels of vitamin D
• Statin side-effects are reduced by Vitamin D – US patent Application – April 2019

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What is cardiac resynchronization therapy - Perplexity AI July 2024

Cardiac Resynchronization Therapy (CRT)
Cardiac Resynchronization Therapy (CRT), also known as biventricular pacing, is a medical treatment designed to improve the heart's rhythm and function in patients with heart failure and arrhythmias. This therapy involves the implantation of a specialized pacemaker that helps the heart's ventricles (the lower chambers) beat in a more synchronized manner.
How CRT Works
CRT involves the use of a device called a biventricular pacemaker. This device is implanted under the skin, typically just below the collarbone, and is connected to the heart via three leads (wires). These leads are strategically placed in the right atrium, right ventricle, and left ventricle (via the coronary sinus) to monitor and regulate the heart's electrical activity. The pacemaker sends small electrical impulses to both ventricles to ensure they contract simultaneously, thereby improving the heart's efficiency in pumping blood.
Types of CRT Devices
There are two main types of CRT devices:

• CRT-P (Cardiac Resynchronization Therapy Pacemaker): This device functions like a standard pacemaker but also delivers electrical impulses to synchronize the ventricles.
• CRT-D (Cardiac Resynchronization Therapy Defibrillator): This device combines the functions of a CRT-P with an implantable cardioverter-defibrillator (ICD). It not only synchronizes the ventricles but also can deliver shocks to correct life-threatening arrhythmias.

Benefits of CRT
CRT can offer several benefits for patients with heart failure, including:

• Improved heart function and efficiency
• Reduced symptoms of heart failure, such as shortness of breath and fatigue
• Enhanced quality of life
• Decreased risk of hospitalization and mortality
• Improved exercise capacity.

Candidates for CRT
CRT is typically recommended for patients who:

• Have moderate to severe heart failure symptoms
• Have an enlarged and weakened heart
• Exhibit dyssynchrony in the heart's ventricles, often indicated by a condition like left bundle branch block
• Have not responded adequately to medication and lifestyle changes.

Risks and Considerations
While CRT is generally considered safe, it does carry some risks, including:

• Infection at the implantation site
• Bleeding or bruising
• Lead displacement or malfunction
• Pneumothorax (collapsed lung)
• Reactions to anesthesia.

Procedure
The implantation of a CRT device involves a minor surgical procedure, usually performed under local anesthesia with sedation. The leads are inserted into the heart through a vein and connected to the pacemaker, which is placed under the skin. The procedure typically requires an overnight hospital stay, and patients can usually resume normal activities within a few days, with some restrictions on heavy lifting and driving.
Follow-Up
After the procedure, regular follow-up appointments are necessary to monitor the device's function and battery life. Adjustments to the device's settings may be made to optimize its performance and ensure the best possible outcomes for the patient.In summary, CRT is a valuable therapy for certain patients with heart failure, helping to improve heart function and quality of life by synchronizing the contractions of the heart's ventricles. It is a well-established treatment option with significant benefits, though it is not suitable for everyone and carries some risks.
References

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Compare Pacemaker and CRT - Perplexity AI July 2024

Feature	Pacemaker	Cardiac Resynchronization Therapy (CRT)
Primary Use	Bradycardia, heart block	Heart failure with ventricular dyssynchrony
Number of Leads	1-2	3 (right atrium, right ventricle, left ventricle)
Target Chambers	Right atrium/ventricle	Both ventricles
Types	Single, Dual, Biventricular	CRT-P, CRT-D
Additional Functions	Basic pacing	Synchronized pacing, defibrillation (CRT-D)
Indications	Slow/irregular heartbeat	Heart failure with reduced ejection fraction
Impact on Heart Function	Maintains regular rhythm	Improves ventricular coordination and efficiency

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VitaminDWiki - Heart Failure patients 4 X less likely to benefit from pacemaker (CRT) if low vitamin D – Oct 2017