A análise prospectiva desse grupo de pacientes poderá determinar o valor do DTC em prever eventos cerebrovasculares com repercussão clínica. Desde o início da coleta de dados, apenas uma paciente teve um AVCi. Essa paciente apresentava DTC normal segundo os critérios do estudo STOP, porém com assimetria e aumento focal da velocidade de fluxo.
Uma comparação de nossos pacientes com uma outra população de adultos falcêmicos foi realizada através de um intercâmbio com Dr. Robert J Adams, da Geórgia, EUA. Não observamos diferenças importantes entre as duas populações estudadas.
Pretendemos também, analisar o impacto de outros métodos de neuroimagem, tais como perfusão por RM, na avaliação e manejo de adultos falcêmicos. Parte dessa análise também já foi realizada.
6 CONCLUSÕES
A avaliação do DTC em adultos com AF neste estudo mostrou:
1. As velocidades de fluxo sangüineo observadas no DTC de adultos com AF são significativamente maiores do que as observadas em adultos saudáveis e menores do que as descritas em crianças com AF.
2. Assimetria e aumento focal da velocidade de fluxo são mais freqüentes na população de adultos falcêmicos do que em voluntários saudáveis e podem representar marcadores de doença arterial.
3. As velocidades de fluxo no DTC se correlacionam inversamente com o hematócrito, tanto em adultos com AF quanto em voluntários saudáveis.
A avaliação da RM e angio-RM de adultos com AF mostrou:
4. A freqüência de alterações na RM de encéfalo e angio-RM das artérias intracranianas em adultos com AF é maior que a descrita na literatura em crianças com AF.
5. História de epilepsia, níveis mais baixos de hematócrito e de HbF e um menor número de transfusões ao longo da vida se associam com alterações específicas na RM.
A correlação entre RM e DTC mostrou:
6. Pacientes adultos falcêmicos com estenoses em território carotídeo diagnosticadas pela angio-RM apresentam velocidades de fluxo no DTC significativamente maiores do que pacientes com angio-RM normais.
7. As velocidades de fluxo associadas a estenoses em adultos com AF são menores do que as descritas em crianças na literatura.
8. A velocidade 160,1 cm/s apresenta alta especificidade na detecção de estenoses em território carotídeo diagnosticadas por angio-RM e pode indicar a necessidade de investigação com exames de neuroimagem em adultos com AF. 9. O DTC e a RM de encéfalo são métodos importantes e complementares na
avaliação da doença cerebrovascular do paciente com AF e apresentam freqüências de alterações e padrões de anormalidades distintos entre crianças e adultos falcêmicos.
ANEXO 3- QUADRO CONTENDO IDADE, HEMATÓCRITO, VELOCIDADES, E AS PRINCIPAIS CARACTERÍSTICAS DA RM E ANGIO-RM DOS PACIENTES IINCLUÍDOS NESTE ESTUDO
Pacientes Idade Hematócrito Vmax Estenose Alteração na RM
1 19 22 113 não não 2 20 20 126 não sim 3 20 25 104 não sim 4 46 20 114 não não 5 28 20 144 não sim 6 43 21 124 não sim 7 23 22 102 . . 8 17 23 111 não não 9 55 25 112 não sim 10 35 24 133 não não 11 45 24 124 sim sim 12 32 24 103 não não 13 17 23 129 não sim 14 20 20 117 não sim 15 28 19 141 não sim 16 30 23 129 não sim 17 22 26 120 não não 18 23 24 123 não sim 19 22 16 121 não sim 20 20 24 109 não não 21 24 28 79 não sim 22 21 24 127 . . 23 20 24 111 não não 24 44 28 107 não sim 25 30 28 70 não sim 26 23 17 100 não sim 27 24 25 105 não não 28 19 29 110 não não 29 23 25 105 não não 30 42 27 157 . . 31 44 27 105 não sim 32 22 22 144 . . 33 42 23 111 . . 34 32 26 97 não sim 35 28 24 103 . . 36 24 24 139 não não 37 28 24 106 não não 38 17 18 157 sim sim 39 17 23 175 sim sim 40 53 23 89 não não 41 22 23 122 não sim
Pacientes Idade Hematócrito Vmax Estenose Alteração na RM 44 18 27 102 não não 45 18 28 105 não não 46 22 26 115 não sim 47 30 27 109 não não 48 23 23 160 não não 49 17 21 130 não não 50 18 26 123 não sim 51 17 23 141 sim sim 52 24 20 91 sim sim 53 23 25 86 não sim 54 22 20 136 não sim 55 27 29 94 não sim 56 28 21 100 não sim
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