Cryoballoon ablation catheterization can evenly and completely “cold kill” the diseased myocardial cell tissue with a small difference in success rate, which is called by experts as the new trend of atrial fibrillation ablation Atrial fibrillation is the most common arrhythmia, and the incidence has reached 0.77%. Because of the catheter radiofrequency ablation means of traditional surgical treatment, serious complications are not rare, so patients are often reluctant to undergo surgery and change to conservative drug therapy, thus paroxysmal atrial fibrillation often develops into persistent atrial fibrillation, increasing the risk of stroke.
At present, an innovative technique, cryoballoon catheter ablation, which is widely used in 600 medical centers in 25 countries and regions, including Europe and the United States, has entered South China and has been successfully practiced in many cases. As the principle of the technique evolves from “burning” to “cold” death of diseased cells and tissues, it is efficient and safe, which relieves patients’ worries.
Successful case: Atrial fibrillation for 10 years, 90-minute ablation “fixed” 59-year-old Mr. Zhang, who was diagnosed with paroxysmal atrial fibrillation for more than 9 years, felt only panic and slow heartbeat in the early days. For fear that atrial fibrillation will form blood clots and make him prone to heart attacks and strokes, Mr. Zhang has been taking medication for anticoagulation and antiarrhythmic treatment as prescribed by his doctor.
After nearly 10 years of “peace and quiet”, Mr. Zhang felt that his symptoms were light, but his heart was shattered by a CT scan: it turned out that his heart had adapted and tolerated a long period of fast heart rate, and began to develop persistent atrial fibrillation, which had led to an enlarged left atrium and cardiac insufficiency. This means that “the medicine is not working”, Mr. Zhang can only receive atrial fibrillation ablation treatment.
At the beginning of this year, in the Department of Cardiology of Guangdong Provincial People’s Hospital, Mr. Zhang underwent a cryoballoon catheter ablation procedure, which was minimally invasive, without surgery, and took only 90 minutes to complete the “cold death” and ablation of myocardial lesion cells. Now, nearly 3 months after the surgery, he does not need to take any more medication, and atrial fibrillation has not come back to haunt him.
The danger of atrial fibrillation is a 5-fold increase in the risk of stroke, but is not the heart rate sometimes beating fast and sometimes beating slow? As the saying goes, “your heart misses a beat when you’re scared”, so what’s the big deal?
Fang Xianhong, chief physician of the Department of Cardiology at Guangdong Provincial People’s Hospital, explained that atrial fibrillation really should not be taken lightly. In principle, the irregular impulses in the atria, resulting in atrial fibrillation, when the heart rate accelerates, the atria can not effectively pump blood, blood stagnation in the atria, the consequence is easy to form blood clots, increasing the risk of heart attack and stroke.
Medical studies have confirmed that atrial fibrillation is a major risk factor for ischemic stroke and death – the risk of stroke is 5 times higher in patients with atrial fibrillation compared to the general population, and 20% of ischemic strokes are associated with atrial fibrillation. Strokes due to AF are more fatal and disabling, with a 2-fold increase in mortality and a 50% increase in severe disability in patients with AF compared to strokes from other causes. In addition, atrial fibrillation can aggravate heart failure.
According to the 2011 study “How to avoid stroke crisis in Asia Pacific”, there are 8 million patients with atrial fibrillation in China, and about 1/3 of them have thrombosis and 3/4 of them have cerebral embolism.
The results of the first large-scale epidemiological study in China showed that the incidence of atrial fibrillation in the whole population in China was 0.77%, and the incidence in people over 80 years old was 7.5%. This also means that atrial fibrillation is more common in older people.
Traditional technology 3 hours to “burn” bad heart muscle cells one by one
Experts say that the traditional non-pharmacological treatment of atrial fibrillation is mainly catheter radiofrequency ablation, which has been popular for nearly 20 years.
Catheter radiofrequency ablation surgery, through the surgical access, the use of cardiac radiofrequency ablation catheter, through the high-frequency current local heating, from far and near, point by point ablation of myocardial lesions that cause atrial fibrillation cell tissue, surgery time often up to three hours or more.
What is more worrying for patients is that not only does the success rate vary greatly depending on the doctor’s level of operation, but there are also serious complications that are not uncommon.
Experts explain that for most patients, radiofrequency ablation is safe and effective, but because radiofrequency energy can destroy the structure and integrity of the endothelium and tissue, which can easily lead to the formation of thrombosis and embolism; excessive heat in radiofrequency can also cause an increase in impedance, and can cause air pressure damage and myocardial perforation.
If the operation is not fine enough, the catheter will also make the local myocardial tissue temperature rise, causing superficial damage to the contact tissue, and at the same time prevent RF energy penetration to the deep tissue, affecting the efficacy of treatment. Clinically, RF is also associated with the risk of cardiac perforation, inconsistent surface and internal myocardial temperatures, phrenic nerve injury, and ablation carbonization/coagulation formation.
Innovative Technology Cryoballoon “freezes” diseased cells
Cryoballoon ablation catheterization, which is widely used in 600 medical centers in 25 countries and regions in Europe and the United States, has accumulated clinical experience of more than 70,000 cases and is a mature and innovative new technology for the treatment of atrial fibrillation. The reporter learned that Guangdong Provincial People’s Hospital is the first hospital in South China to carry out this kind of surgery, and there are seven successful cases.
Fang Xianhong introduced, the same ablation target site lesion tissue, the new technology uses a completely different idea from “hot” to “cold”. The principle of the operation is to introduce a balloon with liquid refrigerant into the target ablation site with a catheter, using the refrigerant to lower the temperature of the lesion and “chill” its cellular tissue.
During the procedure, when cooling, the freezing energy forms ice crystals, which dehydrate the tissue and cause necrosis, while the shear force generated by the ice crystals can directly destroy the lesion cell structure; when rewarming, the ice crystals melt, destroying the microenvironment and drastically reducing the cellular blood supply, making the lesion tissue damage irreversible.
Unlike radiofrequency, cryo-energy can cause transient and reversible tissue damage, greatly reducing the risk of permanent damage to important conduction tissue; the head end of the cryo-catheter adheres to the ablated tissue, and no catheter displacement occurs, improving ablation safety; and cryo-ablation preserves the ultrastructure of tissue cells, thus greatly reducing the risk of thrombosis, pulmonary vein stenosis, and atrioventricular esophageal fistula.
Since cryoablation is less likely to produce thrombus, coupled with the fact that the fibrous connective tissue around the target cells is not destroyed, the surface of the cells at the ablation site is relatively flat and smooth, which also reduces the probability of thrombus adhesion, thus reducing the probability of vascular stenosis and thus reducing recurrent atrial fibrillation.
The advantages of cryoablation also include: minimally invasive intervention, short procedure time, no patient sedation, no pain, and good tolerability.
According to Fang Xianhong, cryoablation is a major trend in the treatment of cardiac arrhythmias in clinical practice. He reminded that the overall drug efficacy of paroxysmal atrial fibrillation is poor, and several studies have shown that the earlier paroxysmal atrial fibrillation is treated, the greater the benefit to the patient, and the more likely to avoid the development of persistent atrial fibrillation.