SAN SALVADOR, El Salvador--(BUSINESS WIRE)--The largest Salvadoran banks have sound buffers against a weak operating environment and asset quality pressures, according to Fitch Ratings. 'While low GDP growth rates constrain credit growth and earnings, and the growth in consumer loans may weaken credit quality, capitalization should remain solid,' says Luis Mauricio Ayala, Associate Director. Credit quality headwinds, tighter liquidity, and potential rating constraints related to the sovereign a