RU2738134C1 - Method for fixation of probe for surgical ablation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to cardiosurgery. Before applying the surgical ablation probe, a single suture is sutured on posterior auricle 3/0 in the area of the supposed fixation of the formed bend of the tip of the probe. Then two ends of thread are pulled through tourniquet. Thereafter, the tip of the probe is inserted between the sutures to a bending level. Tourniquet is tightened and fixed by clamp. Forceps widens available folds of posterior atrium wall from upper or lower angle of atriotomy to bending of fixed tip behind upper or lower left pulmonary vein, applying tip on endocardium, and performing cryoablation.

EFFECT: method enables providing adequate fixation of the probe for surgical ablation on atrial tissue, optimizing the cryoablation procedure, reducing the risk of arrhythmia recurrence, reducing the length of the artificial circulation and surgical intervention.

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Description

The technical field to which the invention relates

The invention relates to the field of cardiac surgery, in particular to a method for fixing a probe for surgical ablation.

State of the art

Atrial fibrillation (AF) is the most common heart rhythm disorder and occurs in 3% of the human population. It doubles the risk of death, 5 times - the risk of stroke, 3 times - the risk of heart failure [1, 2], is the reason for repeated repeated hospitalizations, which requires significant economic costs. Thus, adequate treatment of AF, including surgery, leading to arresting of arrhythmias or reducing its recurrence, is socially and economically feasible.

The modern concept of open surgical treatment of AF is reduced to the application of incisions or isolation lines to the atrial tissue by means of tissue destruction by radiofrequency or cold exposure. Cuts (lines) are made to isolate focal arrhythmia triggers or to create an "electrical labyrinth" to conduct an impulse from the sinoatrial to the atrioventricular node, exclude pathological (so-called fibrillatory) impulse conduction and arrest arrhythmia.

Various schemes of damage (incisions or isolation lines) of the atria are known for use in AF surgery.

Each includes isolation of the pulmonary veins as a key element. Isolation is achieved by ablation around the orifice of each individual vein, around the individual right and left pulmonary veins (bilaterally), or around the orifices of all four pulmonary veins (box).

The latter modification is used alone or as part of a rhythm converting intervention in patients with concomitant AF undergoing open heart surgery.

Insulation lines of damage are applied from the inside of the heart (endocardially) by cold exposure at a temperature of 150 ° C (cryoablation), for this, a Cardioblate CryoFlex probe for surgical ablation (Medtronic Inc., USA) is used. The probe has a flexible tip 10 cm long and 0.3 cm in diameter, the desired shape and curvature of which is formed by the surgeon manually. To perform the "box" scheme, a vertical left atrial atriotomy is performed along the interatrial sulcus. The cut is one of the lines in the diagram. Further, to complete the isolation of the "box", two applications and cold effects are performed with a Cardioblate CryoFlex surgical ablation probe, having previously bent the tip in an L-shape. Cryoablation lines are applied to the posterior wall of the atrium. The first - from the upper corner of the atriotomy, horizontally above the upper pulmonary veins with a change in direction at an angle of 90 ° behind the upper left pulmonary vein downward and ending just below the middle of the distance between the left upper and lower pulmonary veins. In a similar way, the second impact is performed below the lower pulmonary veins with a change in the direction upward behind the lower left pulmonary vein and ending just above the middle of the distance between the left upper and lower pulmonary veins, entering the first isolation line.

The long knee of the probe tip for surgical ablation corresponds to the horizontal cryoablation lines, the short knee to the left vertical.

In practice, just prior to placement on the atrial tissue and cold exposure of the probe for surgical ablation, the tip of the probe is L-shaped. Next, use tweezers to straighten the existing folds of the posterior wall of the atrium, applying the tip to the endocardium. Complete fold expansion for ideal positioning of the probe is not always possible. The uneven shape of the pleated atrial wall and the excessive flexibility of the tip of the surgical ablation probe often prevent it from reaching full contact with the heart chamber wall. The penetration of the atrial folds into the cryotherapy zone leads to the absence of proper tissue damage in the thus compromised area, the appearance of "gaps" in the applied lines, the failure of electrical isolation, and the recurrence of AF. There is a need to apply additional lines of cryotherapy for complete isolation of the electrical isolation of the pulmonary veins, the time of artificial blood circulation and the total time of surgical intervention increase.

Moreover, with long-term mitral valve defect complicated by AF, the left atrium expands several times, the atrial surface area and the distance between the right and left pulmonary veins significantly increase. Excessive posterior atrial wall area in arrested and stuck heart conditions leads to unnecessary folds and even greater technical difficulties in positioning the Cardioblate CryoFlex probe during arrhythmia surgical treatment.

As the closest prototype, the method of fixing the probe for cryobalation, described in the manual for performing the Cryo Maze III Procedure from Medtronic (USA), was chosen [3].

According to the analogue, after the left atriotomy along the Waterstone sulcus, the probe for cryobalation is placed on the lower part of the posterior wall of the left atrium from the lower edge of the atriotomy to the zone between the left pulmonary veins and the auricle of the left atrium, cryoablation is performed, then the probe is placed on the roof of the left atrium from the upper edge of the intersection of the atriotomy with the previous line of damage, cryoablation is performed.

Specialists in the field of cardiac surgery understand that such a method of fixation does not always allow achieving full contact of the probe with the atrial tissue and, therefore, adequate cryoinfluence, due to the folds of the atrial wall resulting from the uneven shape and excess area of the atrium, excessive flexibility of the probe tip for surgical ablation ... This leads to the failure of electrical isolation and recurrence of AF, requires the application of additional cryotherapy lines, increases the time of artificial circulation and the total time of surgical intervention.

Disclosure of the essence of the invention

The object of the invention is to develop a method for fixing a probe for surgical ablation, which avoids its incomplete contact with the atrial wall.

The technical result consists in simplifying the adequate fixation of the probe on the atrial tissue, ensuring the optimal efficiency of cryoablation, reducing the risk of arrhythmia recurrence, decreasing the time of artificial circulation and surgical intervention.

The technical result is achieved by the fact that before the application of the probe for surgical ablation, a single suture is applied to the posterior wall of the atrium with a prolene 3/0 thread in the area of the intended fixation of the formed bend of the probe tip, two ends of the thread are pulled through the turnstile, after which the probe tip is inserted between the threads to the level of the bend , the turnstile is tightened and fixed with a clamp, then the existing folds of the posterior wall of the atrium from the upper / lower angle of the atriotomy to the bend of the fixed tip behind the upper / lower left pulmonary vein are straightened with tweezers, applying the tip to the endocardium, and cryoablation is performed.

Brief Description of Drawings

FIG. 1 shows the posterior wall of the atrium 1 with a single suture 3 superimposed on it in the area of intended fixation 2, by means of a thread 4.

FIG. 2 shows a probe 5 for surgical ablation, placed in the area of the proposed fixation 2, between the threads 4.

FIG. 3 shows a probe 5, and a turnstile 6 with threads 4 threaded into it.

FIG. 4 shows the turnstile 6 in a pressed state against the probe 5. The turnstile 6 is pressed against the probe 5 by pulling the threads 4 from the upper end 7 of the turnstile 6 and by pressing the lower end 8 of the turnstile 6 to the probe 5, accompanied by tightening the seam 3 and pressing the probe 5 to surface 1. Fixation of pressing the probe 5 to surface 1 is carried out by the clamp 9 of the turnstile 6 compressing the walls with threads 4 placed inside, simultaneously clamping the threads 4 and preventing the probe 5 from loosening against the surface 1. The turnstile for pulling the threads is a flexible plastic tube.

Implementation of the invention

The following clinical example illustrates the use of the proposed method for fixing a probe for surgical ablation.

Clinical example:

Patient K, 52 years old. Diagnosis: Connective tissue dysplasia syndrome. Mitral insufficiency of the 3rd degree. Left atriomegaly. From the anamnesis: considers himself a patient since 2016, when shortness of breath appeared during exercise with a gradual decrease in tolerance. Since 2017, AF paroxysms confirmed by Holter ECG monitoring. In August 2018, the patient underwent echocardiography, which revealed mitral insufficiency of the 3rd degree, mitral annulectasia (annulus fibrosus - 39 mm), left atriomegaly (volume of the left atrium 165 ml). On 20.11.2019, the operation was performed: cryoablation of the pulmonary vein orifices in the "box" modification, mitral valve replacement with a mechanical prosthesis St. Jude Medical - 33 mm with partial preservation of subvalvular structures, paraannular plication reduction of the left atrium in conditions of artificial circulation and blood cardioplegia.

After sternotomy, cannulation of the ascending aorta and vena cava, the onset of extracorporeal circulation, cardioplegia, a vertical left atriotomy was performed. A single suture with a prolene 3/0 suture was placed on the posterior wall of the atrium in the area of the proposed fixation of the formed bend of the probe tip, the two ends of the suture were pulled through the turnstile, after which the probe tip was inserted between the threads to the level of the bend, the turnstile was tightened and fixed with a clamp. Then, the existing folds of the posterior wall of the atrium were straightened with forceps from the upper angle of the atriotomy to the bend of the fixed tip behind the upper left pulmonary vein, applying the tip to the endocardium, and cryoablation was performed. A similar method of fixing the tip of the probe for surgical ablation with a suture on the turnstile was performed before applying cold exposure from the inferior angle of the atriotomy, reaching the atrial wall behind the inferior left pulmonary vein.

The further course of the operation was carried out as standard.

The postoperative period was uneventful. The patient was discharged on the 7th day after surgery.

At the follow-up examination after 6 months, the patient showed no active complaints, was active, the work capacity was fully restored, shortness of breath, interruptions in the work of the heart, palpitations did not disturb. According to the studies performed (echocardiography, ECG monitoring by Holter), the function of the prosthesis is normal, there are no rhythm disturbances.

Thus, the claimed method of fixing a probe for surgical ablation avoids technical difficulties during its application, failure of electrical isolation and recurrence of AF, the need to apply additional ablation lines, and reduce the time of artificial circulation and surgical intervention.

Information sources:

1. Krahn AD, Manfreda J, Tate RB, Mathewson FA, Cuddy TE. The natural history of atrial fibrillation: incidence, risk factors, and prognosis in the Manitoba Follow-Up Study. Am J Med. 1995; 98 (5): 476-484. doi: 10.1016 / S0002-9343 (99) 80348-9.

2. Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke. 1991; 22 (8): 983-988. doi: 10.1161 / 01.str.22.8.983.

3. Cryo Maze III Procedure - PDF. https://docplayer.net/23886272-Cryo-maze-iii-procedure.html. Accessed October 13, 2019.

Claims (4)

1. A method of fixing a probe for surgical ablation, characterized in that before the application of the probe for surgical ablation, a single suture is applied to the posterior wall of the atrium in the area of the proposed fixation of the probe, the two ends of the thread are pulled through the turnstile, after which the tip of the probe is inserted between the threads to the level of bending, the turnstile is tightened and fixed with a clamp. 2. A method according to claim 1, characterized in that a single suture in the area of intended fixation is applied with a 3/0 prolene suture. 3. The method according to claim 1, characterized in that the turnstile is made in the form of a flexible plastic tube. 4. The method according to claim 1, characterized in that after tightening the tourniquet and fixing it with a clamp with forceps, the existing folds of the posterior wall of the atrium are straightened from the upper / lower angle of the atriotomy to the bending of the fixed tip behind the upper / lower left pulmonary vein, by applying the tip to the endocardium, and perform cryoablation.

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