Ananda G C
Rheumatic heart disease is one of the most common heart diseases in developing country. One of the most common complications of Rheumatic Heart Disease is Mitral Stenosis which ultimately lead to pulmonary hypertension and heart failure and death. So, PTMC (Percutaneous Transluminal Mitral Commissurotomy) is a well established simple, effective and safe therapeutic intervention for mitral stenosis.
While many literatures reviewed till date have shown that it takes 3-6 months time period for the reduction of pulmonary artery pressure after PTMC, this study is designed to see the result in pulmonary artery pressure immediately after procedure.
Method
Results
It is a prospective observational study on a total of 42 patients who underwent PTMC, 30 were female and 12 were male. Age ranged from 30 to 61 years with the mean age of 45.36±10 years. The mean mitral valve area increased from 0.87±0.2 cm2 to 1.74±0.17 cm2 whereas Mean Pressure Gradient decreased from 13.59± 7.30 mmHg to 5.15±30 mmHg. Mean Pulmonary Artery Pressure decreased from 41.50 ±16.00 mmHg to 33.50±12.00 mmHg. Similarly, the mean left atrial pressure decreased from 26.57±8.62 mmHg to 15.50±5.95 mmHg whereas, the mean Aortic Pressure increased from 91.43 ±23.02 mmHg to 98.29±24.92 mmHg . Eighteen (42.85%) patients had an increase in MR by 2 grades but there is no need of immediate mitral valve replacement. During procedure, paroxysmal PSVT was noted in six (14.285%) patients and also local hematoma was observed in five (11.90%) patients.
Conclusion
There is reduction in pulmonary artery pressure immediately post PTMC which is directly correlated with left atrial pressure without significant MR and tachycardia.
This study is limited in terms of single center with small sample size.
Keywords
Atrial electromechanical delayMitral stenosisP-wave dispersionPercutaneous transvenous mitral commissurotomy.
Introduction
Rheumatic mitral stenosis (MS) is a gained dynamic type of valvular coronary illness, portrayed by diffuse thickening of mitral valve pamphlets, combination of commissures and shortening and combination of chordae tendinae. The mix of mitral valve malady and atrial aggravation, auxiliary to rheumatic carditis prompts left atrial (LA) expansion, fibrosis of atrial divider, and disorder of atrial muscle bundles.1 These basic changes lead to electrical inhomogeneity, non-uniform conduction speeds, and inhomogenous unmanageable periods inside the atrial myocardium.2, 3 The resultant electrical dyssynchrony and electromechanical brokenness are related with expanded danger of atrial fibrillation (AF).4
A few electrocardiographic and echocardiographic markers mirroring the electrophysiological and electromechanical variations from the norm of atria inclined to create AF have been concentrated with a thought of early distinguishing proof of patients who are vulnerable to create AF. Expanded most extreme P-wave span (Pmax) on surface ECG has been accounted for to be related with left atrial size and danger of creating AF.5, 6 P-wave scattering (PWD) is an ECG marker of non-uniform and heterogeneous atrial conduction with ECG leads of various orientation.5 It has been characterized as the distinction among greatest and least P-wave length (Pmax and Pmin). Past examinations have indicated that Pmax and PWD are expanded in patients with rheumatic MS.7, 8
Atrial electromechanical deferral (AEMD) has been characterized as the transient postponement between the identified beginning of electrical action (P-wave on ECG) and the acknowledgment of power in the atrial myocardium (beginning of A′ wave on tissue Doppler imaging (TDI).9 Advances in TDI innovation have encouraged the discovery of atrial mechanical action from various atrial districts with high worldly goals and permitted computation of between and intra-atrial electromechanical delays.10, 11, 12 Prolonged AEMD is considered as a novel marker of atrial electromechanical rebuilding and has been related with expanded AF chance in different illness states including MS.9, 13, 14, 15
Percutaneous transvenous mitral commissurotomy (PTMC) is at present the treatment of decision for patients with indicative serious MS and ideal valve morphology. Fruitful PTMC prompts increment in mitral valve zone (MVA), cardiovascular list, and lessening in transmitral diastolic weight inclination, left atrial weight, left atrial volume, and aspiratory supply route pressures.16, 17 It likewise prompts continued improvement in the practical class of the patients.18, 19 Recent examinations have exhibited that decrease in left atrial weight and help of ceaseless stretch after PTMC turns around left atrial heading subordinate conduction variations from the norm, along these lines expanding the odds of MS patients holding their typical sinus rhythm.20, 21, 22 This investigation was led with a point of contemplating the quick impact of effective PTMC on between and intra-atrial electromechanical deferrals and PWD in patients with extreme rheumatic MS, in ordinary sinus cadence. As far as we could possibly know, there is just a single such investigation distributed in writing so far.23
2. Methods
2.1. Study design
This was a hospital-based prospective, non-randomized, observational study.
2.2. Study population
The examination populace included 25 continuous patients conceded in our emergency clinic with suggestive extreme MS [NYHA class II–IV, MVA of ≤1 cm2 by planimetry, pressure half time (PHT) ≥ 220 ms, as well as mean transmitral diastolic slope (MDG) of ≥10 mmHg],24, 25, 26 in typical sinus beat, with ideal valve morphology (Wilkins' score ≤ 8, no or mellow mitral spewing forth, and no commissural calcification or LA thrombus)27, 28 who experienced a fruitful PTMC (quick post-procedural MVA of ≥1.5 cm2 or ≥50% expansion from pre-procedural MVA, and close to direct mitral disgorging after the procedure).29, 30 Exclusion models included: (I) Documented history or peri-procedural event of AF or some other supported arrhythmia. (ii) Significant contribution of valves other than mitral valve (aortic valve, aspiratory valve, tricuspid valve) or proof of mitral annular calcification on echocardiography. (iii) Known history or clinical proof of coronary supply route ailment, essential cardiomyopathy, left ventricular (LV) brokenness, conduction variations from the norm, pericarditis, thyroid brokenness, iron deficiency, renal disappointment (serum creatinine of >1.5 mg/dl), pneumonic illness, hypertensive cardiovascular sickness, fundamental fiery malady. (iv) Exposure to any known cardiotoxin (for example doxorubicin chemotherapy, ethanol, and so forth.), electrolyte unevenness, utilization of drugs known to influence atrial conduction (for example digitalis, antiarrythmic medications), and patients on pacemakers. (v) Clinical or lab proof of rheumatic movement in going before a half year. (vi) Indiscernible P-waves in multiple leads on the pattern 12-lead ECG. (vii) Past history of any mitral valve mediation (PTMC, shut mitral valvotomy, open mitral valvotomy) or other heart medical procedures.
2.3. Consent and ethical issues
After describing the analysis in depth, informed consent was obtained from each patient. The report was completed by the Committee on Institutional Ethics.
2.4. Pre-procedural evaluation
A detailed clinical history was collected and a thorough physical examination of each patient was conducted upon admission. Baseline tests, including full blood count, serum biochemistry, coagulation profile, serum electrolytes, and chest X-ray, were conducted one day prior to the operation.
2.5. Electrocardiogram (ECG)
On the morning of the day of technique, a 12-lead surface ECG of every patient in recumbent situation at a paper speed of 50 mm/s and 20 mm/mV was gotten to figure the pre-procedural P-wave terms and PWD. The P-wave terms were estimated physically, by an examiner blinded to the clinical subtleties of the patient, utilizing calipers and amplifying focal point (ten times amplification) to characterize the electrocardiographic redirections. The beginning of the P-wave was characterized as the intersection between the isoelectric line and the start of P-wave diversion. The counterbalance of P-wave was characterized as the intersection between the finish of the P-wave avoidance and the isoelectric line. The time inward between the beginning and counterbalance of P-wave was the P-wave term. In every ECG lead, P-wave term was estimated for three back to back P-waves and the mean of three estimations was viewed as the P-wave length of that lead. P-wave span was estimated in each of the 12-ECG leads. Patients with confused P-waves in multiple leads on the pattern 12-lead ECG were rejected from the examination. The longest P-wave length estimated on any of the 12 ECG leads was characterized as the P most extreme (Pmax) and the briefest P-wave span on any lead was characterized as the P least (Pmin). The contrast among Pmax and Pmin was determined and characterized as PWD = Pmax − Pmin. After 24–48 h of the effective PTMC strategy, a comparable ECG was acquired to figure the post-procedural Pmax, Pmin, and PWD.
2.6. Echocardiography
A far reaching pre-procedural echocardiographic assessment of every patient was done in the first part of the day of the day of technique, utilizing an industrially accessible heart ultrasound scanner furnished with 2.5 and 3.5 MHz transducers (Aloka, Prosound, SSD α-110, South Korea), by an accomplished cardiologist who was blinded to the clinical subtleties and aftereffects of different examinations of the patient. Every patient was inspected in the left parallel decubitus and prostrate situation by precordial 2-dimensional, M-mode, Doppler, and tissue Doppler echocardiography as indicated by the rules of American Society of Echocardiography.31, 32 During the echocardiographic assessment, a 1-lead ECG was recorded constantly. A normal of three sequential cycles was investigated for every parameter. Left ventricular end-systolic and end-diastolic breadths (LVIDS and LVIDD) and left atrial (LA) end-systolic distance across were estimated by M-mode imaging in the parasternal long pivot see. LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV), and discharge part (LVEF) were assessed by Simpson's standard in the apical 4-chamber see. MS was evaluated by estimation of MVA by 2D planimetry in parasternal short hub see and by the weight half time technique in the apical 4-chamber see utilizing nonstop wave (CW) Doppler.25, 26 Peak and mean transmitral diastolic weight angles (PDG and MDG) were estimated by ceaseless wave Doppler in the apical four chamber see. Mitral valve morphology and the sub-valvular mechanical assembly were evaluated by 2D imaging, and Wilkins' score was calculated.27, 28 Pulmonary supply route systolic weight (PASP) was determined by including the assessed right atrial strain to {(tricuspid disgorging velocity)2 × 4}, estimated by ceaseless wave Doppler in the apical four chamber view.33 Color stream Doppler imaging was utilized to distinguish and measure the seriousness of mitral spewing forth as indicated by the rules of the American Society of Echocardiography.34
LA volume was determined by the changed Simpson's strategy from the apical four chamber see at end systole, and was amended for body surface region (BSA).35
For the appraisal of between and intra-atrial electromechanical postponements, tissue Doppler echocardiography was performed by enacting the TDI method of a similar machine. TDI was finished with transducer frequencies of 3.5–4 MHz, modifying the ghastly heartbeat Doppler signal channels until a Nyquist cutoff of 15–20 cm/s was reached and utilizing the insignificant optical increase. The screen clear speed was set at 50–100 mm/s to advance the otherworldly showcase of myocardial velocities.9, 10, 11, 12, 13, 14, 15 In the apical four chamber see, the beat Doppler test volume was put at the degree of LV horizontal mitral annulus (Fig. 1), septal mitral annulus (Fig. 2), and right ventricular (RV) tricuspid annulus (Fig. 3). Unique exertion was made to adjust the beat wave cursor so as to keep the Doppler point of rate as near 0° as conceivable to the heading of these dividers. Time span from the beginning of P-wave on surface ECG to the start recently diastolic wave (A′ wave) on TDI, named as PA′, was acquired from horizontal mitral annulus (), septal mitral annulus (), and RV tricuspid annulus (), respectively.9, 10, 11, 12, 13, 14, 15 The contrast between sidelong PA′ and tricuspid PA′ () was characterized as between atrial electromechanical deferral (AEMD); distinction between septal PA′ and tricuspid PA′ () was characterized as right intra-atrial electromechanical postponement (R-IAEMD); and the contrast between parallel PA′ and septal PA′ () was characterized as left intra-atrial electromechanical postponement (L-IAEMD).9, 10, 11, 12, 13, 14, 15
Following the PTMC strategy, a recurrent echocardiogram was performed to survey the post-procedural MVA, nearness and seriousness of mitral spewing forth, pinnacle and mean transmitral diastolic weight inclinations, PASP, and to characterize the accomplishment of method as portrayed previously.29, 30 All patients, in whom PTMC was fruitful, experienced a rehash echocardiographic assessment 24–48 h after the methodology for the estimation of post-procedural LA width; LV measurements, volumes and EF; LA volume; and between and intra-atrial electromechanical postponements.
2.7. PTMC procedure
PTMC was conducted using a typical trans-septic procedure using an Inoue balloon.36 Pre-and post-procedural catheterization data were not included in this analysis.
2.8. Collection and recording of data
All patient data, including demographic, clinical, medical, pre-and post-procedural electromechanical parameters, procedural outcomes, complications, and discharge diagnosis, were recorded in a specially pre-designed patient record form.
2.9. Statistical analysis
Factual examination was performed by SPSS programming bundle (form 20.0, SPSS Inc, Chicago, Illinois, USA). Every single persistent variable were communicated as mean ± SD, and unmitigated factors were accounted for as recurrence and rates. Pearson's connection coefficients were utilized to evaluate the quality of connection between persistent factors. Matched t-test was utilized to consider the distinction of methods for different nonstop factors. Measurable importance was characterized as a p estimation of <0.05.
3. Results
The underlying investigation populace included 30 patients of suggestive extreme MS, in typical sinus mood, who satisfied the other consideration models before the method. Out of these, 5 patients were prohibited from the examination after PTMC (2 patients didn't give assent for the investigation, 1 patient had a fizzled trans-septal cut, 1 patient created extreme post-procedural mitral disgorging, and 1 patient created peri-procedural AF which returned to sinus musicality after DC cardioversion). Last investigation test comprised of the staying 25 patients. Quick procedural achievement rate was 93.3% (peri-procedural AF was not viewed as a procedural disappointment).
3.1. Patient characteristics
The median age of the patients was 34.1 years, from 21 to 45 years. Of the 25 patients enrolled in the study sample, 7 (28%) were male, while 18 (72%) were female. The mean body surface of the patients was 1.45 m2, ranging from 1.29 m2 to 1.75 m2.
3.2. Pre-PTMC parameters
3.2.1. Routine echocardiographic parameters
Pattern echocardiographic parameters of the patients were as per the following: LA breadth – 4.82 ± 0.51 cm; LVIDD – 4.39 ± 0.34 cm; LVIDS – 2.73 ± 0.36 cm; LVEDV – 60.99 ± 10.79 ml/m2; LVESV – 19.37 ± 5.77 ml/m2; LVEF – 68.52 ± 5.48%; Wilkins score – 6.04 ± 1.27; MVA-2D – 0.74 ± 0.13 cm2; MVA-PHT – 0.79 ± 0.14 cm2; PDG – 27.76 ± 6.25 mmHg; MDG – 15.60 ± 4.23 mmHg; PASP – 58.68 ± 13.14 mmHg; and LA volume – 79.0 ± 12.30 ml/m2.
3.2.2. P-wave durations and PWD
Pattern P-wave spans were: Pmax – 136.40 ± 13.19 ms; and Pmin – 91.60 ± 12.48 ms. PWD was 44.80 ± 5.86 ms.
3.2.3. PA′ stretches, Inter-and Intra-atrial electromechanical postponements
Standard PA′ stretches were: – 44.96 ± 5.57 ms; – 106.24 ± 18.48 ms; and – 32.48 ± 4.81 ms. Between and intra-atrial electromechanical postponements were: AEMD – 73.76 ± 15.67 ms; R-IAEMD – 12.48 ± 2.66 ms; and L-IAEMD – 61.28 ± 14.27 ms.
3.3. Pearson correlation analysis of inter- and intra-atrial electromechanical delays (Table 1)
AEMD and L-IAEMD indicated a positive connection with age, LA breadth, Wilkins score, PDG, MDG, PASP, LA volume, Pmax, and Pmin. AEMD and L-IAEMD were contrarily corresponded with MVA. AEMD and L-IAEMD didn't show any noteworthy relationship with PWD. R-IAEMD demonstrated a positive connection with age, LA distance across, and LA volume.
3.4. Impact of PTMC on various parameters
3.4.1. Routine echocardiographic parameters (Table 2)
Immediately after PTMC, there was a statistically significant decrease in LA diameter, LA length, PDG, MDG, and PASP. Statistically significant changes were observed in MVA-2D, MVA-PHT, LVIDD, and LVEDV.
3.4.2. P-wave durations and PWD (Table 3)
There was no change in Pmax, Pmin, and PWD in the immediate post-PTMC phase
3.4.3. PA′ intervals, inter- and intra-atrial electromechanical delays (Table 4)
Statistically significant reductions in,, intervals, AEMD, R-IAEMD and L-IAEMD were observed in the immediate post-PTMC phase.
4. Discussion
The primary discoveries of our examination were:
1. Effective PTMC prompted a measurably noteworthy decline in between and intra-atrial electromechanical postponements.
2. There was no adjustment in P-wave terms or P-wave scattering following PTMC.
3. Between and intra-atrial electromechanical deferrals indicated a solid positive connection with P-wave terms yet not with PWD.
In rheumatic MS, the left atrial life structures, physiology, and electrophysiology are antagonistically influenced optional to expanded left atrial afterload and direct inclusion of left chamber by rheumatic carditis.1, 2, 3, 37 These progressions are related with an expanded danger of improvement of AF which fundamentally builds the drawn out mortality and dreariness of these patients.4, 37, 38
Presented first in 1984 by Inoue et al.,36 PTMC has at present become the treatment of decision in patients with moderate to extreme MS, with good valve morphology, who are indicative or have new beginning AF or noteworthy aspiratory hypertension.39 Over the previous three decades, broad clinical experience has set up the security and adequacy of this methodology in both short and long term.16, 17, 18, 19, 27, 28, 29, 30 Some investigations have indicated that PTMC favorably affects long haul frequency of AF in MS patients.20, 40 In the current examination, we not just portrayed the demonstrated intense hemodynamic advantages of PTMC yet in addition showed its positive impact on novel parameters of left atrial electromechanical rebuilding. We additionally depicted the connection of these parameters with one another and with different clinical and hemodynamic factors.
Our investigation, in consistency with the past entrenched examinations, exhibited noteworthy increment in MVA, LV end-diastolic measurements and end-diastolic volumes, and huge lessening in LA distance across, trans-mitral diastolic weight slopes and PASP following PTMC.16, 17, 18, 19, 27, 28, 29, 30
Expanded Pmax and PWD are notable ECG markers of non-uniform and heterogeneous atrial conduction.13 Various examinations have exhibited their relationship with left atrial size and danger of creating AF.5, 6 Previous examinations have additionally indicated that PWD is expanded in patients with rheumatic MS.7, 8 In an investigation led on patients with mellow to direct MS, Guntekin et al. exhibited that Pmax and PWD increment dynamically as per the movement of MS.41 They likewise indicated that Pmax, Pmin, and PWD were altogether related with MVA, mean mitral slope, LA size, and PASP. In like manner, we likewise found that benchmark Pmax and Pmin had a noteworthy relationship with these parameters. Moreover, we additionally exhibited that Pmax and Pmin had positive relationship with age, Wilkins score, and left atrial volume. These discoveries propose that expanding age and more prominent contortion of mitral valve contraption (reminiscent of more prominent rheumatic action process) and bigger LA volume are related with progressively extreme basic changes in the left chamber, prompting more noteworthy electrical inhomogeneity, non-uniform conduction speeds, and inhomogeneous stubborn periods inside the atrial myocardium, which shows on the ECG as expanded P-wave span. These perceptions are bolstered by the discoveries of Kabukcu et al., who recommended that AF is a marker of boundless rheumatic harm in patients with MS.42 Although PWD was drawn out in our patients, we didn't locate any huge relationship among's PWD and different parameters. Rezaian et al. have additionally mentioned a comparative objective fact in the past.43 They credited this finding to the way that dominant part of the patients in their examination had mellow MS and a generous extent of them were on beta blockers (known to diminish PWD).8 Since we prohibited the patients with non-extreme MS and those taking beta blockers from our investigation, these reasons couldn't clarify our discovering, which needs further explanation. Besides, we didn't watch any adjustment in P-wave terms and PWD in the prompt post-PTMC period. While a few creators have shown an intense abatement in these parameters after effective PTMC,7 others have discovered that such relapse happens to some degree late (≥6 months) after the procedure.44 We accept that surface ECG appearances of deferred and heterogeneous atrial conduction may set aside effort to determine after fruitful alleviation of MS. This needs affirmation on development.
AEMD is a novel, basic, and modest option in contrast to obtrusive electrophysiological reads for evaluating atrial electromechanical remodeling.9, 10, 11, 12, 13, 14, 15 Recent examinations have uncovered that AEMD is delayed in patients with paroxysmal AF and other illness states related with expanded danger of AF.9, 10, 11, 12, 13, 14, 15 These investigations demonstrated that drawn out AEMD appears to reflect atrial renovating for an arrhythmogenic substrate. Ozer et al. exhibited that AEMD is drawn out in patients with MS and is corresponded with PWD.13 They additionally demonstrated that AEMD is connected with left atrial size yet not with the seriousness of MS. Our examination uncovered that AEMD was emphatically connected with age, LA distance across, Wilkins score, trans-mitral weight inclinations, aspiratory supply route pressure, LA volume, Pmax, and Pmin. In spite of the fact that AEMD had a positive connection with PWD, this was not factually huge in our examination. Also, AEMD indicated a negative relationship with MVA. This was as opposed to the perception made by Ozer et al.13 This disparity could halfway be clarified by the reality our patients had progressively extreme MS contrasted with those remembered for that review (MVA – 0.74 ± 0.13 cm2 versus 1.5 ± 0.36 cm2). Univariate relationships of L-IAEMD were like those of AEMD, while R-IAEMD was emphatically connected with age, LA distance across, and LA volume. These discoveries recommend that like P-wave term and PWD, between and intra-atrial electromechanical postponements are markers of left atrial redesigning in patients with MS and drag out dynamically with expanding age, seriousness of MS, and left atrial volumes. Moreover, a solid positive connection between's these electrocardiographic and echocardiographic parameters proposes their reciprocal job in distinguishing patients at expanded danger of creating AF.
We likewise exhibited a noteworthy diminishing in AEMD, L-IAEMD, and R-IAEMD following effective PTMC. Till date, there is just one distributed investigation that has exhibited such a finding.23 Since we didn't watch any comparing decreases in P-wave lengths and PWD, it might demonstrate that TDI is better than surface ECG in mirroring the progressions in atrial electrical milieu after alleviation of MS. Such a hypothesis needs approval by obtrusive electrophysiological contemplates. Another intriguing finding of our investigation was that R-IAEMD added to 17% of the absolute AEMD before PTMC and this commitment expanded to 19% after PTMC. Consequently, in spite of the way that both R-IAEMD and L-IAEMD diminished altogether after PTMC, the decrease altogether AEMD was inferable principally to the reduction in L-IAEMD. This can be intelligently disclosed to be an outcome of decrease in left atrial size and weight following help of MS. The expanded commitment of R-IAEMD to the all out AEMD after PTMC could be estimated to be optional to right atrial volume over-burden because of left to right interatrial shunt over the gained atrial septal deformity. Regardless of whether this commitment changes after the deformity persuades fixed should be tended to in the long haul development.
5. Limitations
The primary constraints of our examination were as per the following:
(I) This examination was completed at a solitary community and the investigation test was moderately little.
(ii) We just examined the quick effect of fruitful PTMC on the electrocardiographic and echocardiographic markers of AF hazard. We by and by don't have any long haul follow-up information of these patients as far as the adjustments in these parameters and their real prescient incentive as to the danger of improvement of AF. Long haul imminent examinations in bigger gatherings of patients are required to come to such complete end results.
(iii) We estimated the conduction times just with TDI and didn't utilize the best quality level, for example electrophysiological study to approve our outcomes.
(iv) At last, it is very much perceived that the improvement of clinical AF is mind boggling and depends on substrate as well as on different factors, for example, triggers and initiators. The impact of inversion of stretch on these different components was not tended to by this investigation.
6. Conclusion
Successful PTMC has a favorable early effect on inter-and intra-atrial electromechanical delays, which are considered to be novel criteria for atrial electromechanical remodeling in MS patients. Prospective large-scale studies are required to confirm whether the change in these markers translates into reduced long-term risk of AF.
Note: This work is partly presented at 31st European Heart and Heart Failure Congress June on 18-19, 2020 held at Paris, France
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