RU2266039C1 - Method for evaluating the severity of chronic cardiac failure - Google Patents

Abstract

FIELD: medicine, cardiology.

SUBSTANCE: one should detect final diastolic size of left ventricle, the size of left atrium, diastolic arterial pressure. Then it is necessary to evaluate the presence of fatigue and dyspnea. Each parameter should be led to obtain a point value. The obtained point values of parameters should be summed up. The severity degree of cardiac failure or its absence should be detected by total summed up value of parameters expressed in points. The innovation enables to standardize the severity degree of cardiac failure and evaluate the quality of therapy conducted more objectively.

EFFECT: higher accuracy of therapy.

5 ex, 4 tbl

Description

The present invention relates to medicine and can be used in therapy and cardiology to diagnose the severity of chronic heart failure (CHF), the effectiveness of the therapy and prognosis in patients with coronary heart disease (CHD).

As an alternative way to assess the severity of heart failure (HF) in modern medicine since 1964, a method of functional classification of heart failure of the New York Heart Association is known. The principles underlying it are based on the assessment of the physical (functional) capabilities of the patient, which can be identified by the doctor with a focused, thorough history, without the use of complex diagnostic equipment.

According to this classification, 4 functional classes (FC) are distinguished:

I FC - the patient does not experience restrictions in physical activity, normal loads do not provoke the occurrence of weakness, palpitations, shortness of breath or anginal pain;

FC II - moderate restriction of physical activity: the patient feels comfortable at rest, but performing normal physical activity causes weakness, palpitations, shortness of breath or anginal pain;

III FC - a pronounced limitation of physical activity: the patient feels comfortable only at rest, but less than usual physical activity leads to the development of weakness, heart palpitations, shortness of breath or anginal pain;

FC IV - inability to perform any load without the appearance of discomfort: symptoms of heart failure or angina pectoris syndrome may appear at rest, discomfort increases when the minimum load is performed (Yu.N. Belenko, V.Yu. Mareev. On the classification of chronic heart failure at the turn of the century. Heart failure: T.2. No. 3. 2000).

For all its simplicity, this classification has its drawbacks, because is subjective in nature and largely depends on the patient’s perception of their well-being and the correct interpretation of these perceptions of the patient by the doctor. In addition, it does not take into account morphological changes in organs and tissues that develop with the progression of heart failure.

Since 1935, Russia has been using a method for determining heart failure, created by V.Kh. Vasilenko and N.D. Strazhesko with the participation of G.F. Lang, based on an assessment of circulatory failure arising from heart failure.

This method is accepted by us as a prototype.

STAGE I - initial, latent circulatory failure, which manifests itself only during physical exertion (shortness of breath, malaise, rapid heartbeat, excessive fatigue). At rest, these phenomena disappear.

STAGE II - severe prolonged circulatory failure, hemodynamic disturbances (congestion in the pulmonary circulation and the pulmonary circulation) appear at rest. In the second stage, two periods are distinguished:

period A - signs of circulatory failure at rest are moderate, hemodynamic disturbance is observed only in one of the sections of the cardiovascular system (in a large or small circle of blood circulation);

period B - the end of a long stage, pronounced hemodynamic disturbances, in which the entire cardiovascular system (and the large and small circle of blood circulation) is involved.

STAGE III - final, dystrophic, with severe hemodynamic disturbances, persistent metabolic changes and irreversible changes in the structure of organs and tissues (Yu.N. Belenkov, V.Yu. Mareev. 2000).

This classification also has its limitations and disadvantages. Different principles are laid at the basis of the separation of stages, whereas it is precisely the single principle that must permeate and unite any systematization. In addition, to date, data have been accumulated characterizing CHF "... as a disease more complicated than it seemed 50 years, and even 20 years ago" (E. Braunwald EHJ, 2001, pp. 625-836).

Therefore, the modern diagnostic procedure does not accurately determine the severity of heart failure, which remains relevant for the further search for diagnostic criteria that can increase the likelihood of establishing its stage.

Tasks - increasing the reliability and accuracy of assessing the severity of heart failure in patients with coronary heart disease.

The essence of the invention is that the significant clinical parameters of the patient's condition include indicators of central hemodynamics: the final diastolic size of the left ventricle, the size of the left atrium, diastolic blood pressure, the presence of weakness and shortness of breath in the patient. Each parameter is assigned appropriate values depending on the severity level - a larger deviation - a higher value: 4-10.1 cm, 3.2-6.8 cm, 60-130 mm.Hq, 0-4, 0-4 and coefficients 88 , 29, 2, 35, 43, then by obtaining the product of the corresponding parameter values by their coefficients, a point estimate of the parameters is determined and the total total is determined, which is taken to determine the severity of heart failure and, with a score of more than 1149, determine the IV severity of heart failure total points from 1149 to 1054 lyayut III severity, with the total score 959 from 1053 to determine the severity of II, with the total points of 958 to 864 determine the severity of I, when the total score is less than 864 determines the absence of heart failure.

To confirm the reliability of the method based on the correlation analysis, indicators were identified that are closely related to each other, the correlation coefficient (r) of which was more than 0.7. This made it possible to single out the main parameters, the influence of which is large, the combination of the rest determines random variations of the studied characteristics, and apply multivariate regression analysis, in which the quantitative changes in the parameters are considered deterministic (nonrandom) values, and the effective observed sign consists of a systematic and random component ( V.Ya. Gelman. Medical informatics. M.: S.-P.burg. 2002. P.455). Of the 56 initially selected indicators, 10 indicators met this selection criterion. CHF severity was calculated using the regression equation

where Y is the point measurement of the observed sign (severity of heart failure);

and ₀ is a free member

a ₁ , a ₂ , ... a _n - regression coefficients of the studied variables;

x ₁ , x ₂ , ... x _n - a set of determinate parameters;

n is the total number of observations of the sign Y.

To determine the regression coefficients a ₀ , a ₁ , a ₂ ... a _{n, we} used data from 3050 patients with coronary heart disease with varying severity of heart failure. This information was processed by Statistica 6.0.

For 10 main parameters: final diastolic size, final systolic size, size of the left atrium, weakness, shortness of breath, diastolic blood pressure, isovolumic relaxation time, thickness of the posterior wall of the left ventricle, thickness of the interventricular septum, heart rate indicator, 5 regression equations were constructed, analysis which showed that the assessment of the severity of heart failure is determined by the number of meters traveled by the patient in 6 minutes. A 6-minute test is a standard technique used to assess exercise tolerance in patients with heart failure (Yu.N. Belenkov, V.Yu. Mareev. Classification of heart failure. T.4. No. 4, 2003. S.5-14 .). The essence of this method is that it measures the distance (meters) that the patient walks for 6 minutes in accordance with his condition. And according to the number of meters passed by the patient, the functional state or functional class of heart failure is determined:

- from 426 to 550 m corresponds to mild CHF (I FC);

- from 300 to 425 m - moderate CHF (II FC);

- from 150 to 300 m - average heart failure (III FC);

- those who were not able to overcome and 150 m - severe heart failure (IV FC).

The following parameters were taken as the main indicators included in the regression equations that evaluate the progression of heart failure: x ₁ - the final diastolic size of the left ventricle (CRD), x ₂ - the size of the left atrium (LP), x ₃ - diastolic blood pressure (ADD), x ₄ - weakness, x ₅ - shortness of breath, x ₆ - thickness of the left ventricular interventricular septum (TMJ), x ₇ - final systolic size of the left ventricle (CSF), x ₈ - thickness of the back wall of the left ventricle (TSC), x ₈ - isovolumic time relaxation (IVRT), x ₁₀ - an indicator of heart rate (HR) (Sheikh-Zadeh Yu.R. A method for determining proper heart rate. Application No. 99106958 for a patent of the Russian Federation, priority from 22.3.99.).

Assessment of the 6-minute test was taken in point terms:

1. <150 m 100 points 2.150-300 m 200 points 3. 300-425 m 300 points 4. 426-550 m 400 points 5.> 550 m 500 points

The resulting regression equation was:

The obtained mathematical model describing the joint venture had a high reliability in terms of the significance level of the Fisher criterion (p <0.0001) and a high degree of approximation, i.e. descriptions of the phenomenon under study (R-square is 0.93). Therefore, this model can be used to assess the severity of heart failure (V.Ya. Gelman. Medical informatics. M .: S.-P.burg. 2002. P.455).

Then, the reliability of the difference in the coefficients of this regression equation from zero, i.e. coefficients having p> 0.05, which are considered to be zero at such a value of p, were removed from the equation (V.Ya. Gelman. Medical informatics. M .: S.-P.burg. 2002. P.455; S. Glants. Statistics. M.: Practice. 1999. S.460).

Thus, the regression that assesses the severity of heart failure can finally be written as

where 1244 is a free member,

88; 29; 1.7; 43; 35.1 - coefficients of the variables (CRC, LP, ADD, shortness of breath, weakness).

For convenience, working with the regression equation (3) identically transformed this equation so that the doctor had to work only with the summation of natural numbers in a quantitative assessment of the severity of heart failure. Round the coefficients to integers and get the equation

Then, the quantity S was added to both sides of equation (4):

S = 88x ₁ ^max + 43x ₄ ^max + 35x ₅ ^max + 29x ₂ ^max = 1339,

where x _i ^{max the} maximum value of the factors x _i , and transfer the free terms to the left side, then equation (4) is written

Y ₂ = 88 (x ₁ ^max -x ₁ ) -29 (x ₂ ^max -x ₂ ) -43 (x ₄ ^max -x ₄ ) -35 (x ₅ ^max -x ₅ ) -2x ₃ ,

where Y ₂ = Y ₁ +95

Correspondingly, the intervals of change of signs (Y) were converted in accordance with the indicators of the 6-minute test depending on the severity of heart failure, then the transformation of equation (4) I group corresponds to the interval Y ₁ ≤190.

As a result, the following values were proposed to determine the four degrees of severity of heart failure:

Y ₁ ≤190, which corresponds to the IV severity of heart failure,

190 <Y ₁ ≤285 - III severity of heart failure 285 <Y ₁ ≤380 - II severity of heart failure 380 <Y ₁ ≤475 - I severity of heart failure Y ₁ > 475 - 0 severity of heart failure

On the other hand, the diagnostic boundaries that determine the severity of heart failure can be represented as follows:

Y ₁ = 1149 (1244-95), which corresponds to the IV severity of heart failure

1149 <Y ₁ ≤1054 (1149-95 or 1244-190) - III severity of heart failure 1054 <Y ₁ ≤959 (1054-95 or 1244-285) - II severity of heart failure 1054 <Y ₁ ≤864 (864-95 or 1244-380) - I severity of heart failure Y ₁ > 864 - 0 severity of heart failure

These diagnostic thresholds that determine the severity of heart failure, simplify and save time for the diagnostic procedure for determining the severity of heart failure.

The method is as follows.

A set of indicators is determined in a patient, including indicators of central hemodynamics: final diastolic size, size of the left atrium, diastolic blood pressure, degree of severity of weakness, shortness of breath are measured. Then, in the diagnostic table, scores are determined that correspond to the obtained values of the symptom of the given patient, these values are written in the third column and summarized, the obtained value and compared with the diagnostic thresholds with a point assessment of the severity of HF. (table 1-4)

Table 1
Indicators of the parameters of the final diastolic size of the left ventricle and the size of the left atrium .. No. Level Point No. Level Point p / p x ₁ -KDR, cm value (KB) p / p x ₂ -LP, cm Value (KB) x ₁ KDR at x ₂ -LP at coefficient 88 ratio 29 BZ = 88x ₁ BZ = 29x ₂ 1. 4.1 361 1. 3.2 93 2. 4.2 370 2. 3.3 96 3. 4.3 378 3. 3.4 99 4. 4,5 396 4. 3,5 102 5. 4.6 405 5. 3.6 104 6. 4.7 414 6. 3,7 107 7. 4.8 422 7. 3.8 110 8. 4.9 431 8. 3.9 113 9. 5,0 440 9. 4.0 116 10. 5.1 449 10. 4.1 119 eleven. 5.2 458 eleven. 4.2 122 12. 5.3 466 12. 4.3 125 thirteen. 5,4 475 thirteen. 4.4 128 14. 5.5 484 14. 4,5 131 fifteen. 5,6 493 fifteen. 4.6 133 16. 5.7 502 16. 4.7 136 17. 5.8 510 17. 4.8 139 eighteen. 5.9 519 eighteen. 4.9 142 19. 6.0 528 19. 5,0 145 20. 6.1 537 20. 5.1 148 21. 6.2 546 21. 5.2 151 22. 6.3 544 22. 5.3 154 24. 6.4 563 23. 5,4 157 25. 6.5 572 24. 5.5 160 26. 6.6 581 25. 5,6 162 27. 6.7 590 26. 5.7 165 28. 6.8 598 27. 5.8 168 29. 6.9 607 28. 5.9 171 thirty. 7.0 616 29. 6.0 174 31. 7.1 625 thirty. 6.1 177 32. 7.2 634 31. 6.2 180 33. 7.3 642 32. 6.3 183 34. 7.4 651 33. 6.4 186 35. 7.5 660 34. 6.5 189 36. 7.6 669 35. 6.6 191 37. 7.7 678 38. 7.8 686 39. 7.9 695 40. 8.0 704 41. 8.1 713 42. 8.2 722 43. 8.4 739 44. 8.5 748 45. 8.6 757 46. 8.7 766 47. 8.9 783 48. 9.0 792 49. 9.1 801 fifty. 9.2 810 51. 9.3 818 52. 9,4 827 53. 9.5 836 54. 9.6 845 55. 9.7 854 56. 9.8 862 57. 9.9 871 58. 10.1 889 Table 2. Indicators of the values of diastolic blood pressure parameters. No. Level Point p / p x _3- ADD, value (KB) mm Hq x ₃ ADD at ratio 2 BZ = 2x ₃ 1. 60 120 2. 65 130 3. 70 140 4. 75 150 5. 80 160 6. 85 170 7. 90 180 8. 95 190 9. 100 200 10. 110 210 eleven. 115 220 12. 120 230 thirteen. 125 240 14. 130 250

Table 3.
Indicators of the parameters of weakness and shortness of breath. No. Level Point No. Level Point p / p x ₄ - weakness value (KB) p / p x ₃ - shortness of breath value (KB) x ₄ weakness at x ₅ shortness of breath with coefficient 43 BZ = 43x ₁ coefficient 35 BZ = 35x ₁ 1. 0 (no) 0 1. 0 (no) 0 2. 1 (weak) 35 2. 1 (weak) 35 3. 2 (moderate) 70 3. 2 (moderate) 70 4. 3 (expressed) 105 4. 3 (expressed) 105 5. 4 (pronounced) 140 5. 4 (pronounced) 140 After that, a general point assessment of the severity of heart failure is made: A SCORE assessment of the degree of severity of heart failure in patients with coronary heart disease. Table 4. Severity of heart failure Scoring of heart failure severity IV > 1149 III from 1149 to 1054 II from 959 to 1053 I from 864 to 958 0 <864

Example:

Patient S. upon admission complained of weakness (weak), periodic pressing pain during physical exertion, interruptions in the work of the heart.

Objectively: The boundaries of relative cardiac dullness are extended to the left to the left midclavicular line. Heart sounds are rhythmic. Systolic murmur is heard on the aorta. II tone on the aorta reinforced. HELL 140/90 mm.Hg., heart rate 66 beats per minute. In the lungs, vesicular breathing, no wheezing. The abdomen is soft, painless. The liver is not palpable. No swelling.

Data of instrumental studies: ECHO-KS KDR 5.3 cm, KSR 3.2 cm, PL 4.1 cm, IVRT 96 ms :, mitral regurgitation 1.5.

After a comprehensive examination, we determined the point value of the signs revealed in the patient: CRD - 5.3 cm, LP - 4.3 cm, ADD - 90 mm.Hq, shortness of breath - no, weakness - 1. Then the values of each symptom were multiplied by the corresponding coefficients and the scores obtained were added up. 88 × 5.3 + 29 × 4.3 + 2 × 90 + 43 × 0 + 35 × 1 = 803. The obtained total score was 803, which, in accordance with the diagnostic threshold that we determined, can be interpreted as the 0 degree of severity of heart failure, i.e. lack of heart failure.

Patient M. complained of shortness of breath (moderate), weakness (weak), periodic rises in blood pressure to 240/120 mm.Hg, accompanied by unpleasant sensations in the heart.

Objectively: The boundaries of relative cardiac dullness are extended to the left to the left midclavicular line. Heart sounds are rhythmic, somewhat muffled. Systolic murmur is heard on the aorta and apex. II tone on the aorta reinforced. HELL 180/100 mm.Hg., heart rate of 75 beats per minute. In the lungs, vesicular breathing, no wheezing. The abdomen is soft, painless. The liver is not palpable. No swelling.

Data of instrumental studies: ECHO-KS: BWW 101 ml, KSO 35 ml, KDR 5.4 cm, KSR 3.2 cm, PL 4.1 cm, IVRT 96 ms, mitral regurgitation 1.5. After a comprehensive examination, we determined the point value of the signs revealed in the patient: CDR - 5.4 cm, LP - 4.1 cm, ADd - 100 mm.Hq, shortness of breath - 2, weakness - 1. Then, the values of each symptom were multiplied by the corresponding coefficients and the scores obtained were added up. 88 × 5.4 + 29 × 4.1 + 2 × 100 + 43 × 2 + 35 × 1 = 915. The resulting total score was 915, which, in accordance with the diagnostic threshold we determined, can be interpreted as I severity of CHF.

Patient B. complained of shortness of breath (severe) during physical exertion, weakness (weak), blood pressure rises to 160/110 mm.Hg, pain in the heart during exertion, periodic swelling on the lower extremities. 2 years ago suffered a myocardial infarction.

Objectively: The boundaries of relative cardiac dullness are extended to the left to the left midclavicular line. Heart sounds are rhythmic. Systolic murmur is heard on the aorta. II tone on the aorta reinforced. HELL 170/100 mm.Hg., heart rate 685 beats per minute. In the lungs, vesicular breathing, in the lower sections is somewhat weakened, there are no wheezing. The abdomen is soft, painless. The liver is not palpable. Pastosity of the legs.

Instrumental research data: ECHO-KS: BWW 170 ml, KSO 101 ml, KDR 5.9 cm, KSR 3.2 cm, PL 4.3 cm, IVRT 96 ms, mitral regurgitation 1.5. After a comprehensive examination, we determined the point value of the signs revealed in the patient: CRD - 5.9 cm, LP - 4.3 cm, ADD - 100 mm.Hg, shortness of breath - 2, weakness - 1. Then the values of each symptom were multiplied by the corresponding coefficients , and the scores obtained were added up. 88 × 5.9 + 29 × 4.3 + 2 × 100 + 43 × 2 + 35 × 1 = 968. The resulting total score was 968, which, in accordance with the diagnostic threshold we determined, can be interpreted as II severity of CHF.

Patient G. complained of shortness of breath (severe), weakness (moderate), fatigue, pain in the heart, constant blood pressure figures 180/100 mm.Hg, interruptions in the work of the heart, swelling of the lower extremities.

Objectively: The boundaries of relative cardiac dullness are extended to the left to the left midclavicular line. Heart sounds are rhythmic, somewhat muffled. Systolic murmur is heard on the aorta. II tone on the aorta reinforced. HELL 180/100 mm.Hg., heart rate 90 beats per minute. In the lungs, vesicular breathing, in the lower sections is not heard, there are no wheezing. The abdomen is soft, painless. The liver is not palpable. Pits from edema in the lower extremities.

Data of instrumental studies: ECHO-KS: BWW 200 ml, KSO 105 ml, KDR 6.1 cm, KSR 5.4 cm, PL 4.4 cm, IVRT 96 ms, mitral regurgitation 2. After a comprehensive examination, the scores were determined revealed in the patient: MDR - 6.1 cm, LF - 4.4 cm, ADd - 90 mm.Hg, shortness of breath - 3, weakness - 2. Then, the values of each symptom were multiplied by the corresponding coefficients and the obtained scores were added up. 88 × 6.1 + 29 × 4.4 + 2 × 100 + 43 × 3 + 35 × 2 = 1063. The resulting total score was 915, which, in accordance with the diagnostic threshold we determined, can be interpreted as III severity of heart failure.

Patient A. complained of weakness (severe), shortness of breath (severe), fatigue, low exercise tolerance, interruptions in the work of the heart, pressing pains in the heart with slight physical exertion, constant blood pressure figures of 170/110 mm.Hg, swelling of the lower extremities.

5 years ago suffered myocardial infarction.

Data of instrumental studies: ECHO-KS: BWW 240 ml, KSO 96 ml, KDR 6.9 cm, KSR 3.2 cm, LP 4.6 cm, IVRT 96 ms: mitral regurgitation 1.5. After a comprehensive examination, we determined the point value of the signs revealed in the patient: CRD - 6.6 cm, LP - 4.3 cm, ADD - 90 mm.Hg, shortness of breath - 3, weakness - 3. Then the values of each symptom were multiplied by the corresponding coefficients , and the scores obtained were added up. 88 × 6.6 + 29 × 4.6 + 2 × 90 + 43 × 3 + 35 × 3 = 1156. The obtained total score was 915, which, in accordance with the diagnostic threshold we determined, can be interpreted as IV severity of heart failure.

Medical and social effect:

The proposed method for assessing the severity of heart failure during use allows you to:

- standardize the determination of the severity of chronic heart failure in patients with coronary heart disease, which is of great importance in determining the working capacity of patients;

- objectively assess the quality of therapy;

- improve the quality of the diagnostic procedure of the early stages of heart failure;

- reduce the frequency of errors in verifying the severity of chronic heart failure;

- to evaluate the high reproducibility of diagnostic indices as criteria for determining the severity of chronic heart failure.

Claims (1)

A method for assessing the severity of chronic heart failure in patients with coronary heart disease, including the determination of significant parameters, characterized in that the following parameters are determined in the patient’s complex: the final diastolic size of the left ventricle is from 4 to 10.1 cm, the size of the left atrium is from 3, 2 to 6.8 cm, diastolic blood pressure from 60 to 130 mm Hg, assess the presence of weakness and shortness of breath by the degree of increase in severity in points from 0 to 4, then the values of the symptoms are multiplied, respectively, by 88, 29, 2, 35, 43 received all values of the parameters are summarized, and the severity of heart failure is determined by the total total value of the points, with a score of more than 1149, the severity of heart failure is determined IV, with a score of 1149 to 1054, 111 severity of heart failure is determined, with a score of 1053 to 959 determine the 11 degree of severity of heart failure, with a score of 958 to 864 determine 1 severity of heart failure, with a score of less than 864 points determine the absence of heart second failure.